Aldosterone is a hormone secreted by the adrenal cortex that regulates electrolyte and water balance by increasing the renal retention of sodium and the excretion of potassium. Recent findings have shown that the physiological functions of the hormone aldosterone go far beyond its well-known role in blood-pressure regulation and salt/water homeostasis. Aldosterone is for example involved in the regulation of inflammation, and also binds directly to mineralocorticoid receptors in specific brain regions. At the late distal tubule and collecting duct, aldosterone has two main actions: 1) aldosterone acts on mineralocorticoid receptors (MR) on principal cells in the distal tubule of the kidney nephron, increasing the permeability of their apical (luminal) membrane to potassium and sodium and activates their basolateral Na+/K+ pumps, stimulating ATP hydrolysis leading to phosphorylation of the pump and a conformational change in the pump exposes the Na+ ions to the outside. The phosphorylated form of the pump has a low affinity for Na+ ions, hence reabsorbing sodium (Na+) ions and water into the blood, and secreting potassium (K+) ions into the urine; 2) aldosterone stimulates H+ secretion by intercalated cells in the collecting duct, regulating plasma bicarbonate (HCO3−) levels and its acid/base balance; and 3) aldosterone may act on the central nervous system via the posterior pituitary gland to release vasopressin (ADH) which serves to conserve water by direct actions on renal tubular resorption.

Epinephrine is a sympathomimetic catecholamine. It acts as a naturally occurring agonist at both alpha and beta-adrenergic receptors. Three pharmacologic types have been identified: alpha 1-, alpha 2-, and beta-adrenergic receptors. Each of these has three subtypes, characterized by both structural and functional differences. The alpha 2 and beta receptors are coupled negatively and positively, respectively, to adenylyl cyclase via Gi or Gs regulatory proteins, and the alpha 1 receptors modulate phospholipase C via the Go protein. Subtype expression is regulated at the level of the gene, the mRNA, and the protein through various transcriptional and postsynthetic mechanisms. Through its action on alpha-adrenergic receptors, epinephrine lessens the vasodilation and increased vascular permeability that occurs during anaphylaxis, which can lead to loss of intravascular fluid volume and hypotension. Through its action on beta-adrenergic receptors, epinephrine causes bronchial smooth muscle relaxation and helps alleviate bronchospasm, wheezing and dyspnea that may occur during anaphylaxis. Epinephrine also alleviates pruritus, urticaria, and angioedema and may relieve gastrointestinal and genitourinary symptoms associated with anaphylaxis because of its relaxer effects on the smooth muscle of the stomach, intestine, uterus and urinary bladder. Epinephrine increases glycogenolysis, reduces glucose up take by tissues, and inhibits insulin release in the pancreas, resulting in hyperglycemia and increased blood lactic acid.

Histamine is a depressor amine derived by enzymatic decarboxylation of histidine. It is a powerful stimulant of gastric secretion, a constrictor of bronchial smooth muscle, a vasodilator, and a centrally acting neurotransmitter. Phosphate salt of jistamine was used as a diagnostic aid for evaluation of gastric acid secretory function. In addition, this compound is used as a positive control in evaluation of allergenic (immediate hypersensitivity or "Type I") skin testing. In addition, histamine is being studied for treatment of multiple sclerosis. It was approved, that histamine physiological functions are mediated by four 7-transmembrane G protein-coupled receptors (H1R, H2R, H3R, H4R) that are all targets of pharmacological intervention. The receptors display molecular heterogeneity and constitutive activity. H1R antagonists are long known antiallergic and sedating drugs, whereas the H2R led to the development of H2R-antagonists that revolutionized stomach ulcer treatment. The H3R is an auto receptor and heteroreceptor providing negative feedback on histaminergic and inhibition on other neurons. The H4R occurs on immuncompetent cells and the development of anti-inflammatory drugs is anticipated.

Equilin sulfate is one of the main component, which is responsible for the pharmacological action of the PREMARIN, conjugated estrogens tablets. Premarin is used to treat the moderate to severe vasomotor symptoms, vulvar and vaginal atrophy due to menopause. It is also used to treat hypoestrogenism due to hypogonadism, castration or primary ovarian failure; to treat breast cancer and advanced androgen-dependent carcinoma of the prostate (for Palliation Only). In addition, premarin is used to prevent postmenopausal osteoporosis. Equilin sulfate is a prodrug, which is hydrolyzed to the corresponding free estrogen equilin, an inhibitor of 17beta-hydroxysteroid dehydrogenase type 1 (17beta-HSD1). Human 17beta-HSD1 catalyzes the reduction of inactive estrone (E1) to the active 17beta-estradiol in breast tissues, is a key enzyme responsible for elevated levels of E2 in breast tumor tissues. Thus equilin reduce the E2 levels in breast tissues and hence the reduce risk of estrogen-dependent breast cancer.