Peripheral Mechanism Involved in Response of Dogs' Cutaneous Veins to Local Temperature Change
The cutaneous veins of the dog constrict and dilate with local cooling and warming, respectively. This response, which is dependent on the integrity of the adrenergic nerves, might be explained by an altered response of the smooth muscle to a given frequency of sympathetic nerve impulses or by local temperature receptors that initiate alterations in sympathetic nerve activity. In the lateral saphenous vein perfused at 42°, 27°, and 17°C, the constriction caused by stimulation of lumbar sympathetic nerves was 40%, 160%, and 200%, respectively, of that at 37°C; the constriction caused by norepinephrine at the same temperatures was 70%, 187%, and 318% of that at 37°C. Division of the dorsal spinal roots from L-1 to S-1 made no difference to the veno-constrictor response to local cooling. It is concluded that an alteration in the sensitivity of the smooth muscle to arriving sympathetic nerve impulses accounts for the venous responses to local temperature changes seen in the intact dog.
- temperature and sympathetic impulses
- norepinephrine and temperature
- veins and norepinephrine
- veins and temperature
- posterior nerve roots and veins
- local temperature and veins
- venomotor reflexes
- Accepted September 30, 1968.
- © 1968 American Heart Association, Inc.