termoregulaci

Termoregulace, or thermoregulation, is the physiological process by which an organism maintains its core body temperature within a narrow optimal range despite environmental temperature changes. In humans and many mammals, the hypothalamus acts as the central thermostat, receiving input from thermoreceptors in the skin and the body’s core. It integrates this information and coordinates effectors to adjust heat production and heat loss.

Heat production is modulated by metabolic rate and, when needed, by shivering and non-shivering thermogenesis in brown adipose tissue. Heat loss occurs via vasodilation of skin blood vessels, increased sweating with evaporative cooling, and behavioral responses such as seeking shade, adjusting clothing, or increasing water intake. Behavioral regulation complements physiological mechanisms and can be rapid or adaptive over days to weeks.

Fever represents a regulated elevation of the body's temperature set point during infection or inflammation, mediated by pyrogens and prostaglandin E2. Temperature regulation involves negative feedback: when core temperature deviates from set point, effectors are activated to bring it back toward normal.

Thermoregulation varies across species. Endotherms maintain relatively stable core temperatures, while ectotherms rely more on environmental temperatures. Several factors influence regulation, including age, pregnancy, health status, medications, ambient humidity, wind, radiant heat, and acclimatization to hot or cold climates.

Clinical relevance includes hypothermia (abnormally low core temperature), hyperthermia (excess heat from environmental or metabolic causes), heat stroke, and fever-related disturbances. Understanding thermoregulation is essential in physiology, medicine, and environmental biology.