Differential responses in post- and pre-ganglionic adrenal sympathetic nerve activity and renal sympathetic nerve activity after injection of 2-deoxy-D-glucose and insulin in rats.
The aim of the study was to compare pre-ganglionic adrenal nerve activity (pre-aSNA) to post-ganglionic adrenal nerve activity (post-aSNA) in rats after administration of 2-deoxy-D-glucose (2-DG, 500 mg kg-1, i.v.), which mimicks a central hypoglycaemia or to the response in pre-aSNA and post-aSNA to hypoglycaemia after injection of insulin (5U). Renal postganglionic sympathetic nerve recordings (rSNA) in a separate group was used as a reference. Adrenal or renal multifibre nerve activity was recorded in chloralose-anaesthetized Wistar-rats. Trimethaphan, a short-lasting ganglionic blocker, was administered i.v. (10 mg kg-1) in order to test for pre- or post-aSNA in the adrenal nerves. The adrenal nerves was considered to contain predominantly post or preganglionic fibres, respectively if the nerve activity in the adrenal nerve decreased (post-aSNA) or increased (pre-aSNA). In contrast, all renal nerves showed almost a pure postganglionic activity. Post-aSNA responded with a tendency to increase after the 2-DG injection. The highest value (percentage change from control) 5 min after injection was 12 +/- 9%. The pre-aSNA increased with values of 99 +/- 52% at 3 min and 86 +/- 31% at 5 min (percentage change from control). The activity in the rSNA was only slightly decreased after the injection of 2-DG when compared to pre-drug control activity. There was a significant difference between the pre-aSNA vs. post-aSNA at 1 min (P less than 0.05), 3 min (P less than 0.01) and 5 min (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
Carlsson
S
S
Department of Physiology, University of Göteborg, Sweden.
Skarphedinsson
J O
JO
Delle
M
M
Hoffman
P
P
Thorén
P
P
D000311:Adrenal Glands / Q000294:innervation*; D000818:Animals; D001786:Blood Glucose / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology; D003847:Deoxyglucose / Q000494:pharmacology*; D004594:Electrophysiology; D007267:Injections; D007328:Insulin / Q000494:pharmacology*; D007668:Kidney / Q000294:innervation*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013564:Sympathetic Nervous System / Q000187:drug effects* / Q000502:physiology
D001786:Blood Glucose; D007328:Insulin; D003847:Deoxyglucose