glucose sensing

Question 1

what brain areas are activated by hypoglycaemia?

Answer 1

thalamus (mediodorsal nucelus)
intermediodorsal nucleus
posterior paraventricular nucleus
hypothalamus
brainstem

Question 2

what are key areas in glucose sensing?

Answer 2

medial amygdalar nucleus (MAN) and ventral medial nucleus (VMN)

Question 3

what is VMN responsible for?

Answer 3

counterregulatory responses in glycaemic changes

Question 4

what are characteristics of MAN and VMN?

Answer 4

control body wt, ovulation, sexual behaviour and fear/anxiety responses

high expression of glucokinase in these areas and well as neural pathways between them, suggests involvement in glucose sensing.

Question 5

describe GABA

Answer 5

main inhibitory receptor in the brain

high levels found in VMH

Question 6

describe GABAergic neurones

Answer 6

GABAergic neurons in the MAN directly project on the VMN

inhibitory tone can modulate the counter regulatory response to hypoglycaemia

GABA projections form the forebrain invovled in energy homeostasis can act on VMH

Question 7

how can glucose secretion in the pancreas be altered?

Answer 7

can be modulated by manipulation of glycaemia within the vMH