Termorregulación en reptiles: mecanismos fisiológicos y neuroendocrinos e implicaciones ecológicas

Thermoregulation represents one of the fundamental physiological processes for the survival, distribution, and biological performance of reptiles, a group mostly composed of ectothermic organisms. This narrative review aims to describe, with theoretical depth, the behavioral, physiological, morphological, neuroendocrine, and cell signaling mechanisms involved in body temperature regulation, as well as to analyze the ecological and evolutionary implications of this process. A literature survey was carried out in scientific databases, selecting primary studies and reviews published between 2000 and 2026. Results demonstrate that reptiles are not merely dependent on environmental temperature; on the contrary, they integrate behavioral (basking, microhabitat selection), physiological (blood flow adjustment, metabolic rate, respiratory control), neuroendocrine (hypothalamic-pituitary-thyroid axis, thyroxine and triiodothyronine action), and muscle cell signaling (excitation-contraction coupling, calcium homeostasis, mitochondrial respiration) responses to maintain body temperature within optimal ranges, usually between 25 °C and 35 °C. The role of thyroxine in modulating basal metabolic rate and mitochondrial ATP and heat production is highlighted, as well as the importance of calcium signaling in muscle cells for adjusting contractile activity and cellular respiration in response to thermal variations. It is concluded that thermoregulation is a multidisciplinary and highly integrated phenomenon, strongly influenced by climate change, with direct impacts on physiology, reproduction, and species conservation.