Related Concept Videos

Hypertension II: Pathophysiology01:29

Hypertension II: Pathophysiology

Hypertension is a chronic condition in which the blood's force against artery walls is excessively high, posing risks such as heart disease. The condition's underlying mechanisms involve complex interactions among the cardiovascular, kidney, and autonomic nervous systems.Renin-Angiotensin-Aldosterone System (RAAS): This system significantly influences blood pressure regulation. When blood pressure decreases, the kidneys secrete renin. This enzyme transforms angiotensinogen, a plasma protein,...
Hypodermis01:02

Hypodermis

The hypodermis (the subcutaneous layer or superficial fascia) is present directly below the dermis. It connects the skin to the underlying fascia (fibrous tissue) of the bones and muscles. It is not strictly a part of the skin, although the border between the hypodermis and dermis can be difficult to distinguish. The hypodermis consists of well-vascularized, loose, areolar connective tissue and adipose tissue, which functions as a mode of fat storage and provides insulation and cushioning for...
Antihypertensive Drugs: Angiotensin-Converting Enzyme Inhibitors01:30

Antihypertensive Drugs: Angiotensin-Converting Enzyme Inhibitors

Angiotensin-converting enzyme (ACE), a vital component of the renin-angiotensin-aldosterone system, is abundant in lung endothelial cells. ACE converts the inactive decapeptide, angiotensin I, into the active octapeptide, angiotensin II. This potent vasoconstrictor narrows blood vessels, increasing resistance to blood flow and elevating blood pressure. Angiotensin II also stimulates aldosterone production, encouraging kidney cells to reabsorb more sodium and water from urine, thereby increasing...
Hormonal Regulation of Blood Pressure01:17

Hormonal Regulation of Blood Pressure

Endocrinal or hormonal intervention in the cardiovascular system is predominantly exerted by the catecholamines - epinephrine and norepinephrine, as well as a slew of hormones that interact with renal function to modulate blood volume.
Epinephrine and Norepinephrine
The adrenal medulla releases epinephrine and norepinephrine, catecholamines that enhance and extend the sympathetic or "fight or flight" physiological response. These hormones escalate heart rate and the force of contraction while...
Hypertension and Regulation of Blood Pressure01:18

Hypertension and Regulation of Blood Pressure

Hypertension, the most common cardiovascular disease, is diagnosed through repeated measurements of elevated blood pressure. Its risks, including damage to the kidney, heart, and brain, are directly proportional to blood pressure levels. Starting from 115/75 mm Hg, the risk of cardiovascular disease doubles with each increment of 20/10 mm Hg. The diagnosis relies on blood pressure measurements, not on patient symptoms, as hypertension is often asymptomatic until end-organ damage is imminent or...
External Anatomy of the Kidney01:21

External Anatomy of the Kidney

The kidneys are a pair of bean-shaped organs in the human body that play a critical role in maintaining overall health. They filter out waste products from the blood, regulate blood pressure, maintain electrolyte balance, and stimulate the production of red blood cells.
The kidneys are located in the retroperitoneal space on either side of the vertebral column, protected posteriorly by the 11th and 12th ribs. The right kidney sits slightly lower than the left owing to the presence of the liver...