Thermoreception, thermoregulation and the early thermal environment
type: CreativeWork
description: Previous investigations1,2 have shown that the capacity of rats and rabbits reared at an elevated environmental temperature to thermoregulate in the cold is impaired. This impairment appears permanent and is associated with other thermoregulatory dysfunction (altered febrile response and altered response to intrahypothalamic noradrenaline injection). The present study investigated the role of the thermal environment in the development of thermoregulatory function by studying the performance of the intact thermoregulatory system and components thereof at different levels of processing of thermal information (thermoreceptive, early integrative and effector levels). The present study confirmed the impaired capacity of heat-reared rats to maintain colonic temperature in the cold and future indicated that this was likely to be attributable to active rather than passive components of the thermoregulatory system. Exposure to an environmental temperature of 20°C for 20 days was able to prevent thermoregulatory dysfunction (as assessed by intrahypothalamic noradrenaline injection) if it occurred after about 14 days of age. Exposure to 20°C was progressively less effective in averting thermoregulatory dysfunction after about 60-80 days of age. The experimental design identified these effects as being of environmental rather than genetic origin. Thermal information processing at the level of the caudal trigeminal nucleus resembled that described at thermoreceptors. The static and dynamic responses of thermoreceptive neurones at this level were quantified and found not to differ between 20°C – and 30°C-reared rats. The distribution of facial thermal receptive fields and the projections of these at the caudal trigeminal nucleus were mapped and also found not to differ. Thermal information originating from truncal skin was intercepted at a midline midbrain level. Data presented here suggested that the sites at which this thermal information could be intercepted included but proba…
abstract: Previous investigations1,2 have shown that the capacity of rats and rabbits reared at an elevated environmental temperature to thermoregulate in the cold is impaired. This impairment appears permanent and is associated with other thermoregulatory dysfunction (altered febrile response and altered response to intrahypothalamic noradrenaline injection). The present study investigated the role of the thermal environment in the development of thermoregulatory function by studying the performance of the intact thermoregulatory system and components thereof at different levels of processing of thermal information (thermoreceptive, early integrative and effector levels). The present study confirmed the impaired capacity of heat-reared rats to maintain colonic temperature in the cold and future indicated that this was likely to be attributable to active rather than passive components of the thermoregulatory system. Exposure to an environmental temperature of 20°C for 20 days was able to prevent thermoregulatory dysfunction (as assessed by intrahypothalamic noradrenaline injection) if it occurred after about 14 days of age. Exposure to 20°C was progressively less effective in averting thermoregulatory dysfunction after about 60-80 days of age. The experimental design identified these effects as being of environmental rather than genetic origin. Thermal information processing at the level of the caudal trigeminal nucleus resembled that described at thermoreceptors. The static and dynamic responses of thermoreceptive neurones at this level were quantified and found not to differ between 20°C – and 30°C-reared rats. The distribution of facial thermal receptive fields and the projections of these at the caudal trigeminal nucleus were mapped and also found not to differ. Thermal information originating from truncal skin was intercepted at a midline midbrain level. Data presented here suggested that the sites at which this thermal information could be intercepted included but proba…
author: Young, Andrew
language: en
license: https://researchspace.auckland.ac.nz/docs/uoa-docs/rights.htm
date published: 1985
date modified: 2026-07-24T01:04:34Z
provider: University of Auckland
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: ResearchSpace@Auckland

PropertyValue
property ID: Handle
value: https://hdl.handle.net/2292/3293