Hyperhomocysteinaemia-induced cardiovascular changes in rats

Area of Science:

• Cardiovascular Physiology
• Endocrinology
• Pharmacology

Background:

• Elevated plasma homocysteine is linked to increased cardiovascular risks.
• Hyperhomocysteinaemia (HHcys) may affect cardiovascular system activity.
• Understanding HHcys effects on cardiovascular function is crucial for risk assessment.

Purpose of the Study:

• To investigate the impact of moderate HHcys on cardiovascular system activity in rats.
• To determine the effects of HHcys on arterial blood pressure, heart rate, baroreflex, and vascular reactivity.
• To explore the role of cardiac sympathetic activity in HHcys-induced hypertension.

Main Methods:

• Male Wistar rats were treated with dl-homocysteine thiolactone (DL-HT) to induce moderate HHcys.
• Cardiovascular parameters including arterial blood pressure, heart rate, and baroreflex gain were measured.
• Vascular reactivity was assessed using pressor and depressor agents, with and without DL-HT washout.

Main Results:

• Moderate HHcys significantly increased baseline arterial blood pressure, heart rate, and baroreflex gain.
• Vascular responsiveness to phenylephrine, sodium nitroprusside, and acetylcholine was altered in HHcys rats.
• HHcys-related hypertension was reversed by atenolol, suggesting increased cardiac sympathetic activity.

Conclusions:

• Moderate HHcys induces significant cardiovascular changes, including hypertension and altered baroreflex activity.
• HHcys affects vascular responsiveness and is associated with increased cardiac sympathetic activity.
• The observed cardiovascular alterations are reversible upon cessation of DL-HT treatment.