Isoprenaline cannot act on pancreatic beta cells without hyperglycemia or alpha-block.
During long-term increase in isoprenaline (pronounced beta-effect) and isoprenaline plus regitine (pure beta-effect) pancreatic insulin-secretion still depended mostly on blood glucose levels. This means that increased beta-effect during normo- or hypoglycemia could not cause a higher insulin-secretion. Only during additional alpha-receptor blockade insulin-secretion was slightly but insufficiently increased. Catecholamines seem to be more regulator than originator of the insulin secretory process.
Porta
S
S
University of Graz, Institute of Functional Pathology, Austria.
Himly
C
C
Rinner
I
I
Schwarz
U
U
Werner
M
M
Poncza
B
B
Korsatko
W
W
D000818:Animals; D001786:Blood Glucose / Q000378:metabolism*; D004837:Epinephrine / Q000097:blood; D007328:Insulin / Q000097:blood*; D007515:Islets of Langerhans / Q000187:drug effects* / Q000378:metabolism; D007545:Isoproterenol / Q000097:blood / Q000494:pharmacology*; D008297:Male; D009638:Norepinephrine / Q000097:blood; D010179:Pancreas / Q000378:metabolism; D010646:Phentolamine / Q000097:blood / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects
D001786:Blood Glucose; D007328:Insulin; D011942:Receptors, Adrenergic, alpha; D007545:Isoproterenol; D009638:Norepinephrine; D004837:Epinephrine; D010646:Phentolamine