Ventromedial nucleus

Cerebro: Ventromedial nucleus Ventromedial nucleus is 'VM', at center, in green. [[Imagen:|250Px|centro|]] Latin nucleus ventromedialis hypothalami Gray's subject # Part of Hypothalamus Components Artery Basilar Vein BrainInfo/UW hier-381 MeSH A08.186.211.730.385.357.352.953 The ventromedial nucleus (sometimes referred to as the ventromedial hypothalamus or VMH) is a nucleus of the hypothalamus."The ventromedial hypothalamus (VMH) is a distinct morphological nucleus involved in feeding, miedo, thermoregulation, y [[sexual activity]]."[1] Contenido 1 Division 2 Function 3 Ver también 4 Referencias 5 External links Division It has four subdivisions: anterior (VMHa) dorsomedial (VMHdm) ventrolateral (VMHvl) central (VMHc). These subdivisions differ anatomically, neurochemically, and behaviorally. Lateral Hypothalamus: This region of the brain is associated with hunger recognition.[2][3] Ventromedial Hypothalamus: This nuclear region is involved with the recognition of the feeling of fullness. Function The ventromedial nucleus (VMN) is most commonly associated with satiety. Early studies showed that VMN lesions caused over-eating and obesity in rats. Sin embargo, the interpretation of these experiments was summarily discredited when Gold's research demonstrated that precision lesioning of the VMN did not result in hyperphagia.[4] No obstante, numerous studies have shown that the immediacy of hyperphagia and obesity syndrome are a consequence of VMN lesions or procaine injections, and point to the VMN's role in satiety.[5][6][7][8][9][10][11] A major review of the subject in 2006 concluded that, "anatomical studies done both before and after Gold's study did not replicate his results with lesions, and in nearly every published direct comparison of VMH lesions vs. PVN or VNAB lesions, the group with VMH lesions ate substantially more food and gained twice as much weight."[12] This strongly substantiates the classification of VMN as the primary satiety center in the hypothalamus. It has also been found that lesions to the VMH in rats caused increased plasma insulin levels. Rats with a VMH lesion compared to normal rats overproduce a circulating satiety factor, to which the control rats can respond and rats with a VMH lesion cannot respond. A lesion to the VMH makes rats overproduce leptin, which they cannot respond to causing them to over eat, leading to obesity.[13] Two researchers, Heterington and Ranson looked at series of twenty-one animals of various degrees of adiposity, with respect to growth appearance, fat distribution, general physical condition, and the correlation between the level of adiposity attained and the correlation of the hypothalamic lesion. Lesions in the hypothalamic area, particularly the region of the ventromedial hypothalamus interrupts a large number of the descending fibers from the hypothalamic cell groups that were found to contribute to obesity in rats.[14] Taylor and Jamshi found that there seems to be a higher concentration of cannabinoid receptor mRNA within the ventromedial hypothalamus in comparison to other nuclei within the hypothalamus. The cannabinoid ingestion has been linked to rewarding processes, and also with the release of dopamine in the brain.[15] VMH is also important in animal play behaviour in mammals. Lesions to VMH along with the hippocampus, amígdala, the cerebellum and the lateral hypothalamus will all reduce play behaviour. In animals the VMHdm has a role in the male animal vocalizations and scent marking behaviors.[16][17][18] The VMHvl plays a role in sexual behaviors in females (lordosis), thus stimulating their sexual arousal.[19][20][21][22] See also Ventromedial hypothalamic syndrome References ↑ Kurrasch, D., & Cheung, C. (2007). The neonatal ventromedial hypothalamus transcriptome reveals novel markers with spatially distinct patterning. The Journal of Neuroscience, 27(50), Retrieved from ↑ The role of the hypothalamus in hunger. ↑ Carlson, N. (2010). Physiology of behavior. (10 Ed., páginas. 355-357). Boston: Allyn and Bacon. ↑ Gold, R.M. (1973). Hypothalamic Obesity: The myth of the ventromedial nucleus. Ciencia 182: 488–490. ↑ Balagura, S., Devenport, L.D. (1970). Feeding patterns of normal and ventromedial hypothalamic lesioned male and female rats. J. Comp Physiol Psychol 71: 357–364. ↑ Becker, E.E., Kissileff, H.R. (1974). Inhibitory controls of feeding by the ventromedial hypothalamus. Am J. Physiol 226: 383–396. ↑ Berthoud, H.R., Jeanrenaud, B. (1979). Changes in insulinemia, glycemia and feeding behavior induced by VMH-procainization in the rat. Res del cerebro 174: 184–187. ↑ Brooks, C.M., Lockwood, R.A., pelucas, M.L. (1946). A study of the effects of hypothalamic lesions on the eating habits of the albino rat. Am J Physiol 147: 735–741. ↑ Epstein, A.N. (1960). Reciprocal changes in feeding behavior produced by intrahypothalamic chemical injections. Am J Physiol 199: 969–974. ↑ Larkin, R.P. (1975). Effect of ventromedial hypothalamic procaine injections on feeding, lever pressing, and other behavior in the rat. J Comp Physiol Psychol 89: 1100–1108. ↑ Maes, H. (1980). Time course of feeding induced by pentobarbital-injections into the rat's VMH. Physiol Behav 24: 1107–1114. ↑ King, Bruce M. (Febrero 2006). The rise, fall and resurrection of the ventromedial hypothalamus in the regulation of feeding behavior and body weight. J Physiol Behav 87 (2): 221–244. ↑ {{ SATOH, N., & OGAWA, Y. (1997). Pathophysiological significance of the obese gene product, leptin, in ventromedial hypothalamus (vmh)- lesioned rats: Evidence for loss of its satiety effect in vmh-lesioned rats*. Department of Medicine and Clinical Science, 138(3), 847-150. Retrieved from html}} ↑ {{ Hetherinton , Un., & Ranson, S. (s.f.). The relation of various hypothalamic lesions to adiposity in the rat. Institute of Neurology, Northwestern University Medical School, 477-481. Retrieved from }} ↑ {{ Jamshidi, N., & Taylor, D. (2001). Anandamide administration into the ventromedial hypothalamus stimulates appetite in rats. Institute of Neurology, Northwestern University Medical School, 134, 1151- 1154. Retrieved from}} ↑ Yahr and Green, 1992 ↑ Flanagan-Cato et al. 2001 ↑ Harding and McGinnis, 2005 ↑ Kow and Pfaff, 1998 ↑ Christensen et al., 1977 ↑ Pfaff and Sakuma, 1979 ↑ Matsumoto and Yamanouchi, 2000 Dugger, et al. (2007). Androgen receptors are required for full masculinization of the ventromedial hypothalamus (VMH) in rats. [1] [2] External links Diagram of Ventromedial motor tract at New Scientist: Seat of female libido revealed (Junio 26, 2006) v·d·e Human brain: diencephalon (TA A14.1.08, Georgia 9.807) Epithalamus Surface Pineal body · Habenula · Habenular trigone · Habenular commissure Grey matter Pretectal area · Habenular nuclei · Subcommissural organ Thalamus Surface Stria medullaris of thalamus · Thalamic reticular nucleus · Taenia thalami Grey matter/ nuclei paired: AN · Ventral (VA/VL, VP/VPM/VPL) · Lateral (LD, LP, Pulvinar) · Metathalamus (MG, LG) midline: MD · Intralaminar (Centromedian) · Midline nuclear group · Interthalamic adhesion White matter Mammillothalamic fasciculus · Pallidothalamic tracts (Ansa lenticularis, Lenticular fasciculus, Thalamic fasciculus) · PCML (Medial lemniscus, Trigeminal lemniscus) · Spinothalamic tract · Lateral lemniscus · Dentatothalamic tract · Acoustic radiation · Optic radiation · Subthalamic fasciculus · Anterior trigeminothalamic tract Medullary laminae Hypothalamus Surface Median eminence/Tuber cinereum · Mammillary body · Infundibulum Grey matter Autonomic zones Anterior (parasympathetic/heat loss) · Posterior (sympathetic/heat conservation) Endocrine posterior pituitary: magnocellular/Paraventricular/Supraoptic (oxytocin/vasopressin) otro: parvocellular/Arcuate (dopamine/GHRH) · Preoptic (GnRH) · Suprachiasmatic (melatonin) Emotion Lateral (hunger) · Ventromedial (satiety) · Dorsomedial (rage) White matter afferent (SN → Medial forebrain bundle) · efferent (Mammillothalamic fasciculus → AN, Stria terminalis → Amygdala, Dorsal longitudinal fasciculus → SC) Pituitary Posterior is diencephalon, but anterior is glandular Subthalamus Subthalamic nucleus · Zona incerta Ventricular system: Third ventricle recesses: (Optic recess, Infundibular recess, Suprapineal recess, Pineal recess) Hypothalamic sulcus · Tela chorioidea of third ventricle Subfornical organ Apertures: Interventricular/Monro Posterior commissure This page uses Creative Commons Licensed content from Wikipedia (ver autores). } ↑ {{ Storlien, L., & Albert, D. (1972). The effect of vmh lesions, lateral cuts and anterior cuts on food intake, activity level, food motivation, and reactivity to taste . Physiology & Behavior, 9(2), 191–192. Retrieved from}} ↑ Template:Carlson, N. (2010). Physiology of behavior. (10 Ed., páginas. 355-357). Boston: Allyn and Bacon.

Si quieres conocer otros artículos parecidos a Ventromedial nucleus puedes visitar la categoría Neuroendocrinology.

Deja una respuesta

Tu dirección de correo electrónico no será publicada.


we use own and third party cookies to improve user experience More information