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Septal Nuclei
The septal area (medial olfactory area), consisting of the lateral septum and medial septum, is an area in the lower, posterior part of the medial surface of the frontal lobe, and refers to the nearby septum pellucidum. The septal nuclei are located in this area. The septal nuclei are composed of medium-size neurons which are classified into dorsal, ventral, medial, and caudal groups. The septal nuclei receive reciprocal connections from the olfactory bulb, hippocampus, amygdala, hypothalamus, midbrain, habenula, cingulate gyrus, and thalamus. The septal nuclei are essential in generating the theta rhythm of the hippocampus. The septal area (medial olfactory area) has no relation to the sense of smell, but it is considered a pleasure zone in animals. The septal nuclei play a role in reward and reinforcement along with the nucleus accumbens. In the 1950s, Olds & Milner showed that rats with electrodes implanted in this area will self-stimulate repeatedly (e.g., press a bar to re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frontal Lobe
The frontal lobe is the largest of the four major lobes of the brain in mammals, and is located at the front of each cerebral hemisphere (in front of the parietal lobe and the temporal lobe). It is parted from the parietal lobe by a Sulcus (neuroanatomy), groove between tissues called the central sulcus and from the temporal lobe by a deeper groove called the lateral sulcus (Sylvian fissure). The most anterior rounded part of the frontal lobe (though not well-defined) is known as the frontal pole, one of the three Cerebral hemisphere#Poles, poles of the cerebrum. The frontal lobe is covered by the frontal cortex. The frontal cortex includes the premotor cortex and the primary motor cortex – parts of the motor cortex. The front part of the frontal cortex is covered by the prefrontal cortex. The nonprimary motor cortex is a functionally defined portion of the frontal lobe. There are four principal Gyrus, gyri in the frontal lobe. The precentral gyrus is directly anterior to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anterior Commissure
The anterior commissure (also known as the precommissure) is a white matter nerve tract, tract (a bundle of axons) connecting the two temporal lobes of the cerebral hemispheres across the midline, and placed in front of the columns of the Fornix of brain, fornix. In all but five species of mammal the great majority of fibers connecting the two hemispheres travel through the corpus callosum, which in Human, humans and all non-Monotreme, monotremes is more than 10 times larger than the anterior commissure. Other routes of communication pass through the hippocampal commissure or, indirectly, via subcortical connections. Nevertheless, the anterior commissure is a significant pathway that can be clearly distinguished in the brains of all mammals. The anterior commissure plays a key role in nociception, pain sensation, more specifically sharp, acute pain. It also contains decussating fibers from the olfactory tracts, vital for the sense of smell and chemoreception. The anterior commis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aromatization
Aromatization is a chemical reaction in which an aromaticity, aromatic system is formed from a single nonaromatic precursor. Typically aromatization is achieved by dehydrogenation of existing cyclic compounds, illustrated by the conversion of cyclohexane into benzene. Aromatization includes the formation of heterocyclic systems. : Industrial practice Although not practiced under the name, aromatization is a cornerstone of oil refining. One of the major reforming reactions is the dehydrogenation of Alkane, paraffins and Cycloalkane, naphthenes into aromatics. The process, which is catalyzed by platinum supported by aluminium oxide, is exemplified in the conversion methylcyclohexane (a naphthene) into toluene (an aromatic). Dehydrocyclization converts paraffins (acyclic hydrocarbons) into aromatics. A related aromatization process includes dehydroisomerization of methylcyclopentane to benzene: : As of alkanes, they first dehydrogenate to olefins, then Cyclization, form rings at t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Follicle-stimulating Hormone
Follicle-stimulating hormone (FSH) is a gonadotropin, a glycoprotein polypeptide hormone. FSH is synthesized and secreted by the gonadotropic cells of the anterior pituitary gland and regulates the development, growth, puberty, pubertal maturation, and reproductive processes of the body. FSH and luteinizing hormone (LH) work together in the reproductive system. Structure FSH is a 35.5 kDa glycoprotein protein dimer, heterodimer, consisting of two polypeptide units, alpha and beta. Its structure is similar to those of luteinizing hormone (LH), thyroid-stimulating hormone (TSH), and human chorionic gonadotropin (hCG). The chorionic gonadotropin alpha, alpha subunits of the glycoproteins LH, FSH, TSH, and hCG are identical and consist of 96 amino acids, while the beta subunits vary. Both subunits are required for biological activity. FSH has a beta subunit of 111 amino acids (FSH β), which confers its specific biologic action, and is responsible for interaction with the follicl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Luteinizing Hormone
Luteinizing hormone (LH, also known as luteinising hormone, lutropin and sometimes lutrophin) is a hormone produced by gonadotropic cells in the anterior pituitary gland. The production of LH is regulated by gonadotropin-releasing hormone (GnRH) from the hypothalamus. In females, an acute rise of LH known as an LH surge, triggers ovulation and development of the corpus luteum. In males, where LH had also been called interstitial cell–stimulating hormone (ICSH), it stimulates Leydig cell production of testosterone. It acts synergistically with follicle-stimulating hormone ( FSH). Etymology The term luteinizing comes from the Latin "luteus", meaning "yellow". This is in reference to the corpus luteum, which is a mass of cells that forms in an ovary after an ovum (egg) has been discharged. The corpus luteum is so named because it often has a distinctive yellow color. The process of forming the corpus luteum is known as " luteinization", and thus the hormone that triggers th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dihydrotestosterone
Dihydrotestosterone (DHT, 5α-dihydrotestosterone, 5α-DHT, androstanolone or stanolone) is an endogenous androgen sex steroid and hormone primarily involved in the growth and repair of the prostate and the penis, as well as the production of sebum and body hair composition. The enzyme 5α-reductase catalyzes the formation of DHT from testosterone in certain tissues including the prostate gland, seminal vesicles, epididymides, skin, hair follicles, liver, and brain. This enzyme mediates reduction of the C4-5 double bond of testosterone. DHT may also be synthesized from progesterone and 17α-hydroxyprogesterone via the androgen backdoor pathway in the absence of testosterone. Relative to testosterone, DHT is considerably more potent as an agonist of the androgen receptor (AR). In addition to its role as a natural hormone, DHT has been used as a medication, for instance in the treatment of low testosterone levels in men; for information on DHT as a medication, see the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glutamate
Glutamic acid (symbol Glu or E; known as glutamate in its anionic form) is an α-amino acid that is used by almost all living beings in the biosynthesis of proteins. It is a Essential amino acid, non-essential nutrient for humans, meaning that the human body can synthesize enough for its use. It is also the most abundant excitatory neurotransmitter in the vertebrate nervous system. It serves as the precursor for the synthesis of the inhibitory gamma-aminobutyric acid (GABA) in GABAergic neurons. Its molecular formula is . Glutamic acid exists in two optically isomeric forms; the optical rotation, dextrorotatory -form is usually obtained by hydrolysis of gluten or from the waste waters of beet-sugar manufacture or by fermentation.Webster's Third New International Dictionary of the English Language Unabridged, Third Edition, 1971. Its molecular structure could be idealized as HOOC−CH()−()2−COOH, with two carboxylic acid, carboxyl groups −COOH and one amine, amino group � ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GABA
GABA (gamma-aminobutyric acid, γ-aminobutyric acid) is the chief inhibitory neurotransmitter in the developmentally mature mammalian central nervous system. Its principal role is reducing neuronal excitability throughout the nervous system. GABA is sold as a dietary supplement in many countries. It has been traditionally thought that exogenous GABA (i.e., taken as a supplement) does not cross the blood–brain barrier, but data obtained from more recent research (2010s) in rats describes the notion as being unclear. The carboxylate form of GABA is γ-aminobutyrate. Function Neurotransmitter Two general classes of GABA receptor are known: * GABAA in which the receptor is part of a ligand-gated ion channel complex * GABAB metabotropic receptors, which are G protein-coupled receptors that open or close ion channels via intermediaries (G proteins) Neurons that produce GABA as their output are called GABAergic neurons, and have chiefly inhibitory action at receptors in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stria Terminalis
The stria terminalis (or terminal stria) is a structure in the brain consisting of a band of fibers running along the lateral margin of the ventricular surface of the thalamus. Serving as a major output pathway of the amygdala, the stria terminalis runs from its centromedial division to the ventromedial nucleus of the hypothalamus. Anatomy The stria terminalis covers the superior thalamostriate vein, marking a line of separation between the thalamus and the caudate nucleus as seen upon gross dissection of the ventricles of the brain, viewed from the superior aspect. The stria terminalis extends from the region of the interventricular foramina to the temporal horn of the lateral ventricle, carrying fibers from the amygdala to the septal nuclei, hypothalamic, and thalamic areas of the brain. It also carries fibers projecting from these areas back to the amygdala. Bed nucleus of the stria terminalis The bed nucleus of the stria terminalis (BNST) is a collection of nuclei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medial Forebrain Bundle
The medial forebrain bundle (MFB) is a neural pathway containing fibers from the basal olfactory regions, the periamygdaloid region and the septal nuclei, as well as fibers from brainstem regions, including the ventral tegmental area and nigrostriatal pathway. Anatomy The MFB passes through the lateral hypothalamus and the basal forebrain in a rostral-caudal direction. The MFB has its main projections to these regions of Brodmann areas (BA) 8, 9, 10, 11, 11m. The superior frontal region of MFB projects to BA 8, 9, 10; the rostral middle frontal projects to dorsolateral prefrontal cortex (BA 9, 10); lateral orbitofrontal of MFB shows its projections to nucleus accumbens septi (NAC) and ventral striatum as subcortical reward associated structures. It contains both ascending and descending fibers. The mesolimbic pathway, which is a collection of dopaminergic neurons that projects from the ventral tegmental area to the nucleus accumbens, is a component pathway of the MFB. The MFB i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paratenial Nucleus
The paratenial nucleus, or parataenial nucleus (), is a component of the midline nuclear group in the thalamus. It is sometimes subdivided into the nucleus parataenialis interstitialis and nucleus parataenialis parvocellularis (Hassler). It is located above the bordering paraventricular nucleus of thalamus and below the anterodorsal nucleus. The paratenial nucleus, like other midline nuclei, receives inputs from a large number of regions in the brainstem, hypothalamus and limbic system. It projects back to an equally wide range, but in a fairly specific manner (in the past, the midline nuclei have often been described as "nonspecific" because of their global effects). Particular targets include medial frontal polar cortex, the anterior cingulate, insula, the piriform and entorhinal cortices, the ventral subiculum, claustrum, the core and shell of nucleus accumbens, the medial striatum, the bed nucleus of stria terminalis, and caudal parts of the central and basal nuclei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Habenula
The habenula (diminutive of Latin meaning rein) is a small bilateral neuronal structure in the brain of vertebrates, that has also been called a microstructure since it is no bigger than a pea. The naming as little rein describes its elongated shape in the epithalamus, where it borders the third ventricle, and lies in front of the pineal gland. Although it is a microstructure each habenular nucleus is divided into two distinct regions of nuclei, a medial habenula (MHb), and a lateral habenula (LHb) both having different neuronal populations, inputs, and outputs. The medial habenula can be subdivided into five subnuclei, the lateral habenula into four subnuclei. Research has shown morphological complexity in the MHb and LHb. Different inputs to the MHb are discriminated between the different subnuclei. In the two regions of nuclei there is a difference in gene expression giving different functions to each. The habenula is a conserved structure across vertebrates. In mammals it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
