Blood pressure, regulatory mechanisms

One rationale for polypharmacy in hypertension is that most drugs evoke compensatory regulatory mechanisms for maintaining blood pressure (see Figures 6-7 and 11-1), which may markedly limit their effect. For example, vasodilators such as... 

Hypotension is the most commonly observed cardiovascular adverse effect of neuroleptic drugs, particularly after administration of those that are also potent alpha-adrenoceptor antagonists, such as chlorpromazine, thioridazine, and clozapine (34). A central mechanism involving the vasomotor regulatory center may also contribute to the lowering of blood pressure. 

Lemmer B. Circadian rhythm in blood pressure Signal transduction regulatory mechanisms and cardiovascular medication. Stuttgart Medpharm Scientific Publishers 1996. p. 91-117. 

Another important urinary regulatory mechanism involves the effects of vasopressin (AVP) also known as anti diuretic hormone (ADH). A decrease in blood pressure or an elevation in plasma osmolality will result in the release of ADH from the posterior... 

Another important regulatory mechanism for urine formation is antidiuretic hormone (ADH), also known as vasopressin, which is released from the posterior pituitary in response to reduced blood pressure and elevated plasma osmolality. In the kidney, ADH acts on the collecting tubule to increase water permeability and reabsorption. As a result, the urine becomes more concentrated, and water is conserved in the presence of ADH. 

The low blood pressure that results from the loss of hydrostatic pressure in the blood vessels triggers the regulatory mechanisms that attempts to restore hydrostatic pressure with vasoconstriction and reserve fluid by decreasing loss through the kidneys and increasing intake. Hypovolemia stimulates... 

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