Desmopressin is a chemical that is similar to Antidiuretic Hormone (ADH), which is found naturally in the body and is produced by the hypothalamus and stored, in the posterior pituitary gland. The main function of ADH is to regulate extracellular fluid volume in the body. ADH secretion is stimulated by angiotensin II, linking it to the renin-angiotensin-aldosterone system (RAAS). ADH stimulates water reabsorption in the kidneys by causing the insertion of aquaporin-2 channels on the apical surface of cells of the distal convoluted tubule and collecting tubules. Desmopressin also causes vasoconstriction through its action on vascular smooth muscle cells of the collecting tubules. It increases urine concentration and decreases urine production. Acetate salt of desmopressin is sold under brand name DDAVP with different formulations: DDAVP Nasal Spray is indicated as antidiuretic replacement therapy in the management of central cranial diabetes insipidus and for management of the temporary polyuria and polydipsia following head trauma or surgery in the pituitary region. It is ineffective for the treatment of nephrogenic diabetes insipidus. DDAVP Injection is indicated for patients with hemophilia A with factor VIII coagulant activity levels greater than 5% and is indicated for patients with mild to moderate classic von Willebrand’s disease (Type I) with factor VIII levels greater than 5%. It was suggested that desmopressin-induced relaxation was mediated by a receptor subtype sharing both V1A and V2 pharmacological profiles.

Desmopressin is a chemical that is similar to Antidiuretic Hormone (ADH), which is found naturally in the body and is produced by the hypothalamus and stored, in the posterior pituitary gland. The main function of ADH is to regulate extracellular fluid volume in the body. ADH secretion is stimulated by angiotensin II, linking it to the renin-angiotensin-aldosterone system (RAAS). ADH stimulates water reabsorption in the kidneys by causing the insertion of aquaporin-2 channels on the apical surface of cells of the distal convoluted tubule and collecting tubules. Desmopressin also causes vasoconstriction through its action on vascular smooth muscle cells of the collecting tubules. It increases urine concentration and decreases urine production. Acetate salt of desmopressin is sold under brand name DDAVP with different formulations: DDAVP Nasal Spray is indicated as antidiuretic replacement therapy in the management of central cranial diabetes insipidus and for management of the temporary polyuria and polydipsia following head trauma or surgery in the pituitary region. It is ineffective for the treatment of nephrogenic diabetes insipidus. DDAVP Injection is indicated for patients with hemophilia A with factor VIII coagulant activity levels greater than 5% and is indicated for patients with mild to moderate classic von Willebrand’s disease (Type I) with factor VIII levels greater than 5%. It was suggested that desmopressin-induced relaxation was mediated by a receptor subtype sharing both V1A and V2 pharmacological profiles.

Mrtoprolol is a beta-adrenergic receptor blocking agent. In vitro and in vivo animal studies have shown that it has a preferential effect on beta-1 adrenoreceptors, chiefly located in cardiac muscle. Clinical pharmacology studies have confirmed the beta-blocking activity of metoprolol in man, as shown by (1) reduction in heart rate and cardiac output at rest and upon exercise, (2) reduction of systolic blood pressure upon exercise, (3) inhibition of isoproterenol-induced tachycardia, and (4) reduction of reflex orthostatic tachycardia. Mrtoprolol is indicated for the treatment of hypertension, angina pectoris and myocardial infarction

Mrtoprolol is a beta-adrenergic receptor blocking agent. In vitro and in vivo animal studies have shown that it has a preferential effect on beta-1 adrenoreceptors, chiefly located in cardiac muscle. Clinical pharmacology studies have confirmed the beta-blocking activity of metoprolol in man, as shown by (1) reduction in heart rate and cardiac output at rest and upon exercise, (2) reduction of systolic blood pressure upon exercise, (3) inhibition of isoproterenol-induced tachycardia, and (4) reduction of reflex orthostatic tachycardia. Mrtoprolol is indicated for the treatment of hypertension, angina pectoris and myocardial infarction

Mrtoprolol is a beta-adrenergic receptor blocking agent. In vitro and in vivo animal studies have shown that it has a preferential effect on beta-1 adrenoreceptors, chiefly located in cardiac muscle. Clinical pharmacology studies have confirmed the beta-blocking activity of metoprolol in man, as shown by (1) reduction in heart rate and cardiac output at rest and upon exercise, (2) reduction of systolic blood pressure upon exercise, (3) inhibition of isoproterenol-induced tachycardia, and (4) reduction of reflex orthostatic tachycardia. Mrtoprolol is indicated for the treatment of hypertension, angina pectoris and myocardial infarction

Mrtoprolol is a beta-adrenergic receptor blocking agent. In vitro and in vivo animal studies have shown that it has a preferential effect on beta-1 adrenoreceptors, chiefly located in cardiac muscle. Clinical pharmacology studies have confirmed the beta-blocking activity of metoprolol in man, as shown by (1) reduction in heart rate and cardiac output at rest and upon exercise, (2) reduction of systolic blood pressure upon exercise, (3) inhibition of isoproterenol-induced tachycardia, and (4) reduction of reflex orthostatic tachycardia. Mrtoprolol is indicated for the treatment of hypertension, angina pectoris and myocardial infarction

Bromocriptine is an ergot derivative with potent dopamine receptor agonist activity, which activates post-synaptic dopamine receptors. Bromocriptine is indicated for the treatment of dysfunctions associated with hyperprolactinemia. Bromocriptine therapy is indicated in the treatment of acromegaly and in the treatment of the signs and symptoms of idiopathic or postencephalitic Parkinson’s disease. It is approved as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus. Some commonly reported adverse reactions include nausea, fatigue, dizziness, vomiting and headache. Bromocriptine may interact with dopamine antagonists, butyrophenones and certain other agents.

Verapamil is a FDA approved drug used to treat high blood pressure and to control chest pain. Verapamil is an L-type calcium channel blocker that also has antiarrythmic activity. The R-enantiomer is more effective at reducing blood pressure compared to the S-enantiomer. However, the S-enantiomer is 20 times more potent than the R-enantiomer at prolonging the PR interval in treating arrhythmias. Verapamil inhibits voltage-dependent calcium channels. Specifically, its effect on L-type calcium channels in the heart causes a reduction in ionotropy and chronotropy, thuis reducing heart rate and blood pressure. Verapamil's mechanism of effect in cluster headache is thought to be linked to its calcium-channel blocker effect, but which channel subtypes are involved is presently not known.

Tamoxifen (brand name Nolvadex), is selective estrogen receptor modulators (SERM) with tissue-specific activities for the treatment and prevention of estrogen receptor positive breast cancer. Tamoxifen itself is a prodrug, having relatively little affinity for its target protein, the estrogen receptor (ER). It is metabolized in the liver by the cytochrome P450 isoform CYP2D6 and CYP3A4 into active metabolites such as 4-hydroxytamoxifen (4-OHT) (afimoxifene) and N-desmethyl-4-hydroxytamoxifen (endoxifen) which have 30–100 times more affinity with the ER than tamoxifen itself. These active metabolites compete with estrogen in the body for binding to the ER. In breast tissue, 4-OHT acts as an ER antagonist so that transcription of estrogen-responsive genes is inhibited. Tamoxifen has 7% and 6% of the affinity of estradiol for the ERα and ERβ, respectively, whereas 4-OHT has 178% and 338% of the affinity of estradiol for the ERα and ERβ. The prolonged binding of tamoxifen to the nuclear chromatin of these results in reduced DNA polymerase activity, impaired thymidine utilization, blockade of estradiol uptake, and decreased estrogen response. It is likely that tamoxifen interacts with other coactivators or corepressors in the tissue and binds with different estrogen receptors, ER-alpha or ER-beta, producing both estrogenic and antiestrogenic effects. Tamoxifen is currently used for the treatment of both early and advanced estrogen receptor (ER)-positive (ER+) breast cancer in pre- and post-menopausal women. Additionally, it is the most common hormone treatment for male breast cancer. Patients with variant forms of the gene CYP2D6 (also called simply 2D6) may not receive full benefit from tamoxifen because of too slow metabolism of the tamoxifen prodrug into its active metabolites. Tamoxifen is used as a research tool to trigger tissue-specific gene expression in many conditional expression constructs in genetically modified animals including a version of the Cre-Lox recombination technique. Tamoxifen has been shown to be effective in the treatment of mania in patients with bipolar disorder by blocking protein kinase C (PKC), an enzyme that regulates neuron activity in the brain. Researchers believe PKC is over-active during the mania in bipolar patients.

Tamoxifen (brand name Nolvadex), is selective estrogen receptor modulators (SERM) with tissue-specific activities for the treatment and prevention of estrogen receptor positive breast cancer. Tamoxifen itself is a prodrug, having relatively little affinity for its target protein, the estrogen receptor (ER). It is metabolized in the liver by the cytochrome P450 isoform CYP2D6 and CYP3A4 into active metabolites such as 4-hydroxytamoxifen (4-OHT) (afimoxifene) and N-desmethyl-4-hydroxytamoxifen (endoxifen) which have 30–100 times more affinity with the ER than tamoxifen itself. These active metabolites compete with estrogen in the body for binding to the ER. In breast tissue, 4-OHT acts as an ER antagonist so that transcription of estrogen-responsive genes is inhibited. Tamoxifen has 7% and 6% of the affinity of estradiol for the ERα and ERβ, respectively, whereas 4-OHT has 178% and 338% of the affinity of estradiol for the ERα and ERβ. The prolonged binding of tamoxifen to the nuclear chromatin of these results in reduced DNA polymerase activity, impaired thymidine utilization, blockade of estradiol uptake, and decreased estrogen response. It is likely that tamoxifen interacts with other coactivators or corepressors in the tissue and binds with different estrogen receptors, ER-alpha or ER-beta, producing both estrogenic and antiestrogenic effects. Tamoxifen is currently used for the treatment of both early and advanced estrogen receptor (ER)-positive (ER+) breast cancer in pre- and post-menopausal women. Additionally, it is the most common hormone treatment for male breast cancer. Patients with variant forms of the gene CYP2D6 (also called simply 2D6) may not receive full benefit from tamoxifen because of too slow metabolism of the tamoxifen prodrug into its active metabolites. Tamoxifen is used as a research tool to trigger tissue-specific gene expression in many conditional expression constructs in genetically modified animals including a version of the Cre-Lox recombination technique. Tamoxifen has been shown to be effective in the treatment of mania in patients with bipolar disorder by blocking protein kinase C (PKC), an enzyme that regulates neuron activity in the brain. Researchers believe PKC is over-active during the mania in bipolar patients.