Some morphological observations on the heart of adult wistar rats following exposure to aqueous extract of ocimum gratissimum

Cardiovascular Diseases (CVD) continue to be one of the leading causes of deaths despite recent advancements in the medical therapies. This study assessed the effect of crude aqueous extract of Ocimum gratissimum commonly used for the treatment of diarrhoea, urinary infections, fever and dysentery on heart morphology. Twenty-four Wistar rats of both sexes with average weight of 175g were used. The rats were randomized into four groups each containing 6 rats. Groups B, C and D received the aqueous extract of Ocimum gratissimum orally at doses of 0.7g/kg, 1.4g/kg and 2.8g/kg body weight respectively for 3 consecutive weeks. Group A served as control group which received distilled water only. After the 3 weeks of administration, the rats were sacrificed by cervical dislocation and the hearts were dissection, blood samples were taken for haematological analysis for blood platelet and the organs were fixed in 10% formol saline for histological investigation by light microscopy. Histological observation was normal in control group. Treated sections showed distortions, disaggregation and loss of cellular components. Haematological findings showed significant differences between control and treated groups and revealed that Ocimum gratissimum is capable of invoking an inflammatory response that transits from acute to chronic on persistent administration. The heart weights of the treated rats also increased compared with the control.