Angiostenin II receptors do not contain the side effect of dry cough:
Angiotensin-II receptor antagonist do not show the side effect of dry cough as like the other ACE-inhibitors because-
Angiotensin-II receptor antagonists have a selective effect on the Angiotensin-II receptor and no effect on the bradykinin or prostaglandin levels. On the other hand ACE-inhibitors (e.g., Captopril, Enalapril, etc) not only exert influence on the Angiotensin converting enzyme but also prevent breakdown of badykinin, and since badykinin stimulates prostaglandin synthesis, prostaglandin levels are also increase. Increased level of both bradykinin as well as prostaglandin are responsible for this bothersome side effect. About 5%-20% patients are face this side effect.
Peptide mimetics :-
Peptide mimetics can be defined as the molecules which mimic the activity or show activity of peptides but have no peptide bonds.
Characteristics-
1- No peptide bonds between amino acids
2- Molecular weight is less than 700 Daltons
There are many process for designing peptide mimetics. The most rational method is the “de novo peptide mimetic design”
Peptide mimetics are the new era drug for the hypertension treatment. It has a upper hand over the ACE-inhibitors. The main reasons for designing peptide mimetics are-
1- Bioavailability is actually very high.
2- Prolong duration of action of hypertensive drug.
3- Show more stability than the ACE-inhibitors.
A brief description about the general pattern for designing peptide mimetics is given below-
- Initially, the amino acid which comprise the pharmacophore of the peptide must be identified .Thus a knowledge of the structure- activity relationship for the peptide under consideration is essential.
- In the second step of this de novo design process, the proper spatial arrangement of the pharmacophoric groups must be elucidated. NMR sprectroscopy, X-ray defraction studies and molecular modeling programs which allow for energy minimizing procedures and molecular dynamics stimulation can be used to construct a model of the biologically active conformation.
- In the final step of the process, the pharmacophoric groups must be mounted on a non peptide template in such a manner that they retain the proper spatial arrangement found in the original peptide.
Gallstone
Gallstone
