Hypothalamus and Feeding – Lecture 16

30 fill-in-the-blank flashcards covering key hormones, neural circuits, and regulatory mechanisms of feeding and energy balance.

The three components of the hypothalamic response are , , and .

humoral, visceromotor, somatic motor

The hormone , produced by adipose tissue, signals body fat levels to the brain.

leptin

Leptin activates /CART neurons in the arcuate nucleus to promote satiety.

α-MSH

Leptin inhibits /AgRP neurons in the arcuate nucleus to reduce hunger.

NPY

is the precursor protein that is cleaved to generate α-MSH.

POMC

α-MSH exerts its anorexigenic action by activating the receptor.

MC4R

The peptide antagonizes MC4R and stimulates feeding.

AgRP

MC4 receptors are highly expressed on neurons of the nucleus and lateral hypothalamus.

paraventricular

Lesion of the hypothalamic area (LHA) causes aphagia and weight loss.

lateral hypothalamic area

Lesion of the nucleus (PVN) leads to hyperphagia and obesity.

paraventricular nucleus

The intestine-derived peptide that reduces meal size in response to fatty foods is .

cholecystokinin (CCK)

After a meal, blood levels of rise 2–4 fold within an hour to inhibit appetite.

GLP-1 (glucagon-like peptide-1)

The stomach-derived hunger hormone released during fasting is .

ghrelin

The hypothesis proposes that the brain defends a set level of body fat.

lipostatic

The ob gene encodes the hormone .

leptin

The db gene encodes the for leptin.

leptin receptor

In parabiosis, an ob mouse loses weight when joined to a WT mouse because it receives circulating .

leptin

In parabiosis, a WT mouse starves when joined to a db mouse because the db mouse overproduces .

leptin

The hypothalamic peptide (aka hypocretin) increases appetite and promotes wakefulness.

orexin

Among the listed peptides, α-MSH is anorexigenic, whereas is orexigenic.

ghrelin

High leptin levels increase activity of the nervous system to raise energy expenditure.

sympathetic

Low leptin levels preferentially activate the nervous system to promote energy storage.

parasympathetic

A high-fat diet elevates the phosphatase , which blocks leptin and insulin signaling.

PTP1B (protein tyrosine phosphatase 1B)

The anti-obesity drug Zepbound mimics the gut hormones GLP-1 and .

GIP (glucose-dependent insulinotropic polypeptide)

The somatic motor response to elevated leptin involves inhibition of hunger neurons in the hypothalamic area.

lateral hypothalamic area (LHA)

Ghrelin exerts its orexigenic effect by activating receptors on hypothalamic /AgRP neurons.

NPY

NPY/AgRP neurons inhibit POMC neurons by releasing the neurotransmitter .

GABA

With aging, innervation of POMC neurons by fibers increases, contributing to leptin resistance.

AgRP

Low leptin inhibits pituitary release of ACTH and .

TSH

Leptin functions as an signal in the negative feedback loop regulating body fat.

afferent