Generation and processing of peripheral temperature signals in mammals

Abstract

A BST RACT. --Temperature transduction in peripheral cold receptors and processing of peripheral temperature signals in the spinal cord were studied in cats and rats. The temperature dependence of the generator potential is attributed to different temperature coefficients of an electrogenic Na-effiux and the passive Na-influx. Cold receptor activity and particularly its bursting pattern is considerably modulated by the local Ca-concentration, but the effect of elevated Ca-concentration is abolished by the ATPase blocker ouabain. --The peripheral temperature signals from the scrotal skin of rats are transformed in dorsal horn neurones (DHN) into temperature reactions, which occur only above (warm reaction) or below (cold reaction) a certain temperature threshold and are limited to an operational range of 1-4°C. Convergency of different temperature inputs were observed in one and the same DHN. Supraspinal control of temoerature reactive DHN appears to be complex but predominantly excitatory.

Body-core temperature decreases during hypoxic hypoxia in Long–Evans and Brattleboro rats

“…197 1 ;Iriki and Simon 1973) and skin temperature in our experiments. These changes may have stimulated cutaneous thermoreceptors (Hensel 1976;Pierau et al 1980;Sumins and Dubner 1981) to effect the changes in GC that we observed. Increases in central levels of adenosine (Laudignon et al 1991;Phillis et al 1987;VanWylen et al 1986;Ticho and Radulovacki 1991 ;Wang et al-1992) md (or) histamine (Sudhakaran et al 1979;Wada et id.…”

The effects of nucleus raphe magnus lesions on an ascending thermal pathway in the rat.

“…Stimulation of the nucleus raphe magnus has no effect on the spinal trigeminal neurones which respond to facial skin temperature (Dawson, Dickenson, Hellon & Woolf, 1981). There is evidence, however, that the scrotal skin temperature responsive neurones in the dorsal horn of the rat 316 SCROTAL THERMAL PATHWA Y AND RAPHE MAGNUS spinal cord are subject to tonic descending control (Pierau, Neya, Yamasato & Ulrich, 1980). Cooling the thoracic spinal cord, which reversibly blocks descending pathways, decreases the intrinsic firing rate of 60% of the scrotal temperature-responsive neurones in the spinal cord but the activity of the remaining temperature-responsive neurones is usually increased.…”

Activity patterns of temperature-reactive dorsal horn neurons and their reactions to peripheral receptor stimulation by Ca.

“…Three neurons were identified as inverse warm-reactive because the scrotal skin warming produced an inhibition and the cooling restored the intrinsic activity in the pre-warming period without inducing any facilitation (HELLON and MISRA, 1973a). Figure 3 shows the static activity of 29 neurons of the static and dynamic/ static warm-reactive type as a function of the scrotal temperature.In most of (PIERAU et al,1980).As is demonstrated in Fig.4…”