Hypericum perforatum L. treatment restored bone mass changes in swimming stressed rats.

Unlabelled: Stress, via corticosteroids release, influences bone mass density. Hypericum perforatum (Hp) a traditional remedy possess antidepressive activity (serotonin reuptake inhibitor) and wound healing properties. Hp preparation contains mainly hypericin, hyperforin, hyperoside and flavonoids exerting oestrogen-mimetic effect.

Nifedipine-induced histological changes in the parotid glands of hypertensive rats.

Nifedipine is a widely used anti-anginal and anti-hypertensive agent. It is associated with significant gingival changes attributed more to collagen hyperplasia than to enhancement of protein synthesis. We investigated the influence of nifedipine on morphological changes in the parotid glands of rats in a model of hypertension.

The influence of simvastatin in rats mandible and femur bone mass under Freund's adjuvant arthritis.

OBJECTIVES. Complete Freund's Adjuvant (CFA)-induced arthritis in rats has been used widely as a model of rodent arthropathy and polyarthritis followed by osteoporosis, decreased bone formation and increased bone formation. Osteoporosis is characterized by rapid reduce of bone mass affecting more than 100 million people worldwide.

Stress can affect drug pharmacokinetics via serum/tissues protein binding and blood flow rate alterations.

Binding of drugs to plasma and tissue proteins is critically involved in their pharmacokinetics and pharmacodynamics. Stress affects drugs' protein binding via alterations in plasma proteins' levels and excessive increase of free fatty acids due to cortisol-induced fat mobilisation. Free fatty acids play a crucial antagonistic role to drugs for the binding sites on albumin, the major binding plasma protein, resulting in subtherapeutic or toxic levels of many medications' pharmacological classes (oral anticoagulants, beta-lactames, fluoroquinolones, local anaesthetics).

L-cysteine's effect on modulated rat brain enzymes with forced swimming.

Background: Forced exercise is associated with oxidative stress, and L-cysteine (L-cys) administration reduces free-radical production.

Aim: To investigate whether L-cys (5 mg/kg) intraperitoneal administration can ameliorate modulated total antioxidant status (TAS), protein concentration, and the activities of acetylcholinesterase (AChE), (Na+,K+)-ATPase, and Mg2+-ATPase in rat brain after 2 and 3 hr of forced swimming.

Methods: TAS, protein, and enzyme activities were measured spectrophotometrically before and after 2 and 3 hr of exercise without or with L-cys administration.

The role of the protein-binding on the mode of drug action as well the interactions with other drugs.

Drug transport and disposition are influenced by a non-specific and reversible drug binding to plasma and tissues proteins. Albumin and al acid glycoprotein are the most important transport proteins of the blood. Albumin possesses specific sites for acidic and basic drug binding and can interact with them in the plasma since a third site is trapped only by digoxin.