Dorsomedial hypothalamic nucleus

Function

The dorsomedial hypothalamic nucleus (DMH) receives its circadian information from the suprachiasmatic nucleus, both directly and via subparaventricular zone, and senses leptin and other feeding cues, but it is also possible that it contains its own feeding-entrained oscillator (FEO). This still has yet to be proven in vitro. The DMH sends information to the ventrolateral preoptic area, locus coeruleus, and orexinergic neurons in order to aid in the regulation of wakefulness. The DMH is also involved in the regulation of hypothalamic outflow to the autonomic nervous and endocrine systems. Almost all major nuclei and areas of the hypothalamus feed information to the DMH.

The DMH is also known as a stress center. The inhibition of neuronal activation using muscimol in the DMH inhibited 85% of heart rate response and 68% of blood pressure response to air stress. This displays that the DMH plays a role in the increase of heart rate and blood pressure as cardiovascular responses to stress. Such sympathetic responses to psychological stress, including elevation of body temperature, are driven by a descending neural pathway from the DMH to sympathetic premotor neurons in the rostral raphe pallidus nucleus (rRPa) of the medulla oblongata. A study in 2020, discovered a psychosomatic neural pathway from the dorsal peduncular cortex (DP) in the medial prefrontal cortex to the DMH that drives a variety of physiological responses to psychological stress. The DMH is also a part of the pathway corticotrophin-releasing hormone (CRH) takes when it is secreted by the paraventricular nucleus of the hypothalamus, and it is involved in the flow from the sympathetic nervous system to the adrenal gland.