JNTU B.Pharmacy IV EXPERIMENTAL PHARMACOLOGY Previous Question Paper (September - 2022 - R17)

Terminal blood collection methods in mice are performed under deep anesthesia and are followed by euthanasia. Two common methods are:

1. Cardiac Puncture: The animal is placed in dorsal recumbency. A needle is inserted into the heart, typically through the thoracic wall, and blood is withdrawn directly from the ventricle. This method provides a large volume of high-quality blood but requires significant technical skill to avoid clotting or hemolysis.
2. Axillary or Retro-orbital Bleeding: Axillary bleeding involves severing the axillary vessels after the animal is deeply anesthetized. Retro-orbital bleeding involves inserting a capillary tube into the medial or lateral canthus of the eye to puncture the retro-orbital sinus. Both methods are efficient for obtaining terminal samples but must be performed strictly according to ethical guidelines to ensure the animal remains unconscious throughout the procedure.

Transgenic models are considered superior for experimentation because they allow for the precise manipulation of the genome, enabling researchers to study specific gene functions, disease mechanisms, and therapeutic interventions in a living system. Their advantages include:

• Disease Modeling: They can mimic human genetic diseases more accurately than induced models, providing a better understanding of disease pathogenesis.
• Targeted Research: Researchers can introduce specific mutations (knock-in) or delete specific genes (knock-out) to observe the resulting phenotype, which helps in identifying drug targets.
• Predictive Value: These models often provide more reliable data regarding drug efficacy and safety, as they reflect the biological consequences of specific genetic alterations, leading to more translational success in clinical trials.
• Specificity: They reduce experimental variability by providing a controlled genetic background, ensuring that observed effects are directly linked to the genetic modification.