Essentials of cell physiology

Cell physiology and molecular genetics now provide the basis for the fundamental understanding of the mechanisms involved in normal and pathological physiology, modes of drug action, and risks involved in surgical procedures. Some explanations, often involving a single mutation in a protein are straightforward (e.g. cystic fibrosis transmembrane conductance regulator (CFTR) in cystic fibrosis). Others may involve a constellation of effects (e.g. obesity) and surprisingly there still remain important areas lacking comprehensive explanation (e.g. the mode of action of general anaesthetics) or close to resolution but still lacking detail (aldosterone controlling both K and Na regulation in the kidney). The present article presents a concise summary of regulation of cell function, concentrating on the cell membrane and important organelles. Signalling and second messengers, together with the role of membrane channels and transporters constitute an important aspect of this, mediated via kinases and phosphatases. Cell volume regulation, reflecting swelling and oedema, are an important aspect of organ transplantation and brain function.