Convergence and Divergence, a Concept for Explaining Drug Actions

Abstract

Abstract. For the teaching and / or learning about drug actions and for the discovery and development of new drugs, it is important to understand how drugs act on living bodies. So far, there has been no clear description on the general principle of drug action in pharmacology textbooks. We propose two principles to depict the action mechanism of drugs. The first is that most, if not all, drugs act on proteins at the molecular level, that is, enzymes, receptors, ion channels, and transporters. The second is that a drug may cause divergent or convergent responses, resulting in changes of a physiological or pathological function of the human body. The concept of divergence and convergence can be used to explain the complex individuality of drug actions.

Alcohol and pregnenolone interaction on cerebral arteries through targeting of vascular smooth muscle Ca2+- and voltage-gated K+ channels of big conductance

“…To investigate the possibility that EtOH and PREG constrict MCA through a common pathway, we used a wide range of PREG concentrations (10 nM–100 µM [ 19 ]) in the presence and absence of 50 mM EtOH. If the two cerebrovascular constrictors were acting through a common pathway, then submaximal concentrations of PREG in combination with EtOH at 50 mM would show additivity in constricting the MCA [ 46 ]. Since we have previously documented that MCA constriction by either agent does not require the endothelium, but is mediated by targets and mechanisms located in the vascular SM [ 19 , 29 ], MCA segments were de-endothelialized before pressurization, as described in the Materials and Methods section.…”

“…To investigate the possibility that EtOH and PREG constrict MCA through a common pathway, we used a wide range of PREG concentrations (10 nM-100 µM [19]) in the presence and absence of 50 mM EtOH. If the two cerebrovascular constrictors were acting through a common pathway, then submaximal concentrations of PREG in combination with EtOH at 50 mM would show additivity in constricting the MCA [46]. Since we have previously documented that MCA constriction by either…”

Real World Problems in Developing a Critical Thinking Approach to Learning in Pharmacology

“…Although these students are generally high performing and motivated, it became apparent through assessment instruments that too much emphasis was placed on knowledge of facts and information. Pharmacology is an interdisciplinary science that requires central knowledge of basic sciences including biochemistry, anatomy and physiology and clinical medicines (Watanabe et al, 2004).…”