Category: Physiology

Pharmacokinetics, the study of how the body handles drugs, confirms that approximately 90% of all drugs are eliminated from the body by the kidneys after being metabolized by the liver. The complex journey detailing what is the process of clearing all drugs from a person's body involves several intricate biological steps known as absorption, distribution, metabolism, and excretion (ADME).

Oxytocin, often referred to as the "love hormone," plays a vital role in childbirth, lactation, and social bonding. Understanding **what is the primary mechanism of action of oxytocin** reveals how this small, nine-amino-acid peptide can have such profound physiological and neurological effects. The process fundamentally relies on triggering an increase in intracellular calcium levels within target cells.

In the United States, over 70 million prescriptions for NSAIDs—a primary class of prostaglandin inhibitors—are written each year [1.4.2]. Understanding **what happens if prostaglandins are inhibited** is key to grasping both the therapeutic benefits and the significant physiological risks involved.

Endothelin-1 is widely regarded as the most potent vasoconstrictor produced by the body, capable of inducing intense, prolonged blood vessel narrowing. Alongside it, Angiotensin II plays a critical role in the regulation of blood pressure, making these two chemicals powerful vasoconstrictors with significant physiological and pathological effects.

Erythropoietin (EPO) is a hormone primarily produced by the kidneys that is crucial for regulating the production of oxygen-carrying red blood cells. Understanding **what does EPO do to the body** is essential for comprehending its therapeutic applications in treating anemia and the dangers associated with its misuse.

Less than 1% of all white blood cells are basophils, yet they, along with mast cells, are the critical cells responsible for answering the question: **What secretes heparin to prevent blood clotting?**. These specialized immune cells store and release heparin to regulate blood flow and inflammation at sites of injury.

Did you know that the "fight-or-flight" response is primarily orchestrated by the stimulation of **alpha and beta receptors** throughout the body? These specialized cellular structures act as key communication hubs for the autonomic nervous system, regulating crucial involuntary functions like heart rate, blood pressure, and respiratory activity.

As core body temperature drops, heart rate decreases proportionally, with some studies in therapeutic hypothermia showing a reduction of around 10 beats per minute for every degree Celsius lost. This slowing, known as hypothermic bradycardia, is a direct and predictable physiological response to cold exposure, explaining why hypothermia leads to bradycardia.

Over 600 specific medications, including many common over-the-counter drugs, exhibit unintended anticholinergic effects. This occurs due to their fundamental mechanism of blocking a key neurotransmitter, leading to a wide range of side effects that disrupt normal bodily functions.

Anhidrosis, or the inability to sweat, is a well-documented side effect of the medication atropine, significantly impacting the body's ability to regulate temperature. This occurs because atropine blocks the specific nerve signals that command sweat glands to produce sweat. Understanding what does atropine do to sweat is crucial for managing this effect, particularly in hot weather or during physical exertion, where overheating and heatstroke are significant risks.