From the Guidelines
Body temperature regulation is controlled by the hypothalamus in the brain, which acts like the body's thermostat, maintaining core temperature around 98.6°F (37°C) through a balance of heat production and heat loss mechanisms, as supported by recent guidelines 1.
Mechanisms of Body Temperature Regulation
The mechanisms of body temperature regulation involve:
- Heat production: The body produces heat through metabolic processes, such as cellular respiration, and through muscle activity, such as shivering 1.
- Heat loss: The body loses heat through various mechanisms, including:
- Radiation: Heat is lost through radiation from the skin to the environment 1.
- Convection: Heat is lost through convection, where warm air rises and is replaced by cooler air 1.
- Evaporation: Heat is lost through evaporation of sweat from the skin 1.
- Conduction: Heat is lost through conduction, where the body comes into contact with a cooler object or surface 1.
Thermoregulatory System
The thermoregulatory system involves complex feedback loops where temperature-sensitive neurons in the skin and core send signals to the hypothalamus, which then coordinates appropriate responses to maintain homeostasis, including:
- Vasodilation: Blood vessels near the skin dilate to increase blood flow to the surface, allowing heat to radiate away from the body 1.
- Vasoconstriction: Blood vessels constrict to reduce heat loss when the body is too cold 1.
- Sweating: Sweat glands activate, producing moisture on the skin that evaporates and cools the body 1.
- Shivering: Muscles shiver to generate warmth when the body is too cold 1.
- Non-shivering thermogenesis: Brown fat tissue is activated in cold conditions to generate heat through non-shivering thermogenesis 1.
Hormonal Influence
Hormones like thyroxine influence basal metabolic rate, affecting overall heat production, and play a crucial role in maintaining body temperature homeostasis 1.
Clinical Implications
Disruptions to the thermoregulatory system can result in conditions like hypothermia or hyperthermia, which can be life-threatening if severe, and require prompt medical attention to prevent morbidity and mortality 1.
From the Research
Mechanisms of Body Temperature Regulation
The human body maintains a constant internal temperature through a complex process involving the hypothalamus and sensory receptors throughout the body. The key mechanisms of body temperature regulation include:
- Heat production and heat loss, which are balanced to maintain a stable body temperature 2
- The hypothalamus, which acts as the primary regulator of body temperature, receiving input from sensory receptors and controlling the body's thermoregulatory responses 2, 3
- Neural pathways that communicate temperature information from the periphery to the brain, and central circuits that coordinate the homeostatic response 3
Thermoregulatory Processes
The body's thermoregulatory processes involve:
- The regulation of heat loss through sweating and vasodilation 4
- The regulation of heat production through shivering and non-shivering thermogenesis 4
- The integration of temperature information from the periphery and the brain to control the body's thermoregulatory responses 3, 5
Role of Specific Neural Pathways
Specific neural pathways, such as the ventral part of the lateral preoptic nucleus (vLPO) and the dorsal part of the dorsomedial hypothalamus (DMD), play a crucial role in regulating body temperature 5. The vLPO GABAergic neurons suppress the thermogenic effect of DMD neurons, reducing body temperature in response to a thermal challenge 5.
Factors Influencing Body Temperature Regulation
Various factors, including intrinsic factors (morphology, heat adaptation, biological sex, and age), diseases (neurological, cardiovascular, metabolic, and genetic), and injuries (spinal cord injury, deep burns, and heat stroke), can influence the regulation of deep body temperature during heat stress 4. Additionally, certain medications, such as acetaminophen, can elicit hypothermia through the activation of specific receptors, such as TRPA1 6.