Adaptive changes in thermoregulation and their neuropharmacological basis

Area of Science:

• Physiology
• Neuroscience
• Thermoregulation

Background:

• Adaptive changes in thermoregulation include morphological and functional modifications.
• Morphological changes (body shape, insulation) take months to years, while functional changes (effector capacity, regulatory characteristics) are faster.
• Functional changes involve short-term (minutes) and long-term (weeks) modifications in thermoregulatory responses' threshold and gain.

Purpose of the Study:

• To review evidence for the involvement of monoaminergic brain stem systems in adaptive thermoregulation.
• To explore how these systems modulate thermoregulatory responses based on recent insights and experimental data.
• To elucidate the role of central monoamines in processing thermal information and modifying effector outputs.

Main Methods:

• Review of electrophysiological, neuropharmacological, and neuroanatomical studies.
• Analysis of insights into the organization of the thermoregulatory system.
• Evaluation of experimental evidence on monoaminergic system involvement.

Main Results:

• Monoaminergic brain stem systems participate in adaptive thermoregulation.
• These systems modulate thermal information processing at multiple sites, including hypothalamic neurons.
• Serotonin and noradrenaline act antagonistically on hypothalamic neurons, influencing thermoregulatory responses.
• Interconnections between monoaminergic systems and peripheral feedback mechanisms optimize vegetative responses.

Conclusions:

• Central monoamines are key modulators of adaptive thermoregulation, influencing thermal input, integration, and output.
• Antagonistic actions of serotonin and noradrenaline in the hypothalamus are crucial for fine-tuning thermoregulation.
• Cross-adaptive changes in thermoregulation can be explained by these interrelations, linking nonthermal factors to thermal responses.