Peptide Hormones of the Heart Natriuretic Factors

ANP now belongs to a family of natrinreteic peptides that also includes BNP (brain natrinretic peptide) and CNP (C-type natriuretic peptide). BNP and CNP have different N- and C-termini to ANP. CNP has a shorter N-terminal than either ANP or BNP. CNP has less natriuretic and diuretic activity than ANP or BNP. 

ANP receptors have been isolated and characterized. Three receptor subtypes, termed ANP, ANPg, and ANP, have been described. The ANP receptor is a 120 kDa protein with ANP and BNP as its primary ligands the ANPg receptor has CNP as its primary ligand. The ANP and ANPg receptors are coupled to guanylyl cyclase the ANPj, receptor is not. 

The natriuretic peptides have a short t 2 when administered systemically. They are rapidly metabolized by the nentral endopeptidase (NEP) enzyme. When ANP is administered, there is a prompt and profound increase in nrine flow and sodinm excretion. 

Systemic arterial hypertension ( high blood pressure ) does not typically make the afflicted individual feel unwell however, after many years, it leads to vascular damage and to the secondary complications thereof hence, the designation of hypertension as the silent killer. The ultimate aim of the pharmacological management of hypertension is to prevent these complications and thus to prolong not only life expectancy but also quality of life. 

Neurotransmitter receptors as messenger targets (e.g., adrenergic drugs such as p-blockers, chapter 4) 

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