Abstract
In K-loaded intact and nephrectomized control dogs there is a four-to five-fold increase
of basal serum insulin. With beta receptor blockade in K-loaded intact animals the
increase of basal serum insulin is less than Πto that in controls; in those with
nephrectomy, the increase is similar to that in controls. Cervical vagotomy in K-loaded
intact dogs does not alter (influence) the increase of serum insulin; in those with
nephrectomy there is a striking increase. In K-loaded intact dogs cervical vagotomy
added to beta receptor blockade has no influence i.e., the response is the same as
that to blockade alone; in those with nephrectomy, the increase produced by vagotomy
is suppressed. Results suggest that in controls with nephrectomy, the insulin secretory
response does not involve beta receptors of pancreatic islet B cells owing to restraint
by efferent impulses in the cervical vagi. Interruption of the impulse by vagotomy
releases the restraint, with resulting hyperactivity; the accompanying hyperinsulinemia
may be the result of suppression of the hyperactive receptors by beta receptor blockade.
Key words
Beta Receptor Blockade - Cervical Vagotomy - Efferent Vagal Impulses - Nephrectomy
- Pancreatic Islet B Cells
