Pharmacology 2 Midterm Post-Lab Discussion Exp 6-9

III Experiment # 3 Blood Collection

Blood Collection Guidelines

  • Recommended blood volumes aim to maintain the health of the animal and validity of experimental results.

  • Guidelines are applicable to healthy, normal adult animals.

  • Special consideration for young, aged, stressed, and diseased animals; they might not tolerate recommended blood volume withdrawals.

Methods of Blood Collection in Mice

Without Anesthesia

  • Saphenous Vein: 25-gauge needle used for small volume blood collection.

  • Dorsal Pedal Vein: 23/27-gauge needle used to obtain small blood volume.

With Anesthesia

  • Tail Cut: Sharp scissors/scalpel to remove 1-2mm of tail distal to coccygeal vertebrae.

  • Orbital Sinus: Pasteur pipette/microhematocrit tube used to collect blood from retro-orbital venous sinus.

  • Jugular Vein: 22-gauge needle with 1mL syringe to withdraw blood from anesthetized animal.

  • Submandibular Vein: Lancet used to puncture the vascular bundle that drains the face.

Terminal Procedures

  • Cardiac Puncture: 22-gauge needle and 3mL syringe for blood collection directly from the heart of anesthetized animals.

  • Posterior Vena Cava, Axillary Vessels: Other advanced techniques for terminal blood collection.

Blood Collection Volume Guidelines

  • Total circulating blood volume averages 5.5-8.0% of animal's body weight.

  • Non-terminal blood collection limited to 10% of total blood volume at a single collection or every two weeks for serial collections.

Estimated Total Blood Volume and Safe Bleeding Volume of Selected Species

Species

Blood volume (ml/kg)

Max Bleeding - 10% (ml/kg)

Cat

55

5.5

Cattle

55

5.5

Chicken

60

6.0

Dog

86

8.6

Mouse

79

7.9

III Experiment # 6 Analgesic Property

Understanding Pain

  • Defined by the International Association for the Study of Pain as an "unpleasant sensory and emotional experience associated with actual or potential tissue damage."

Analgesics

  • Agents relieving pain by elevating pain threshold without disturbing consciousness.

Screening Methods for Analgesics

  • Centrally Acting Analgesics: Hot Plate Method, Tail Clip Method, Tail Immersion Test, Radiant Heat Method, among others.

  • Peripherally Acting Analgesics: Randall-Selitto Test, Writhing Test.

Types of Analgesics

Narcotic Analgesics

  • Potent, effective for severe pain.

  • Act on the central nervous system by binding to opioid receptors. Examples include Morphine, Methadone, Codeine.

Non-Narcotic Analgesics

  • Relieve pain without narcotic effects; may also act as anti-inflammatory agents. Examples include Aspirin, Ibuprofen, Acetaminophen.

Advantages of NSAIDs

  • Help reduce inflammation and manage pain without significant addiction risks.

  • Higher margin of safety and well absorbed; food does not substantially impact bioavailability.

III Experiment # 7 Antispasmodic Property

Definition of Antispasmodics

  • Substances relieving muscle tension and spasms, acting primarily on smooth muscles of hollow organs. Typically do not cause sedation.

Classification

Antimuscaranics

  • Includes drugs like Hyoscine, Dicyclomine, which block cholinergic transmission at parasympathetic postganglionic nerve endings.

Smooth Muscle Relaxants

  • Drotaverine selectively inhibits phosphodiesterase 4, affecting cyclic adenosine monophosphate levels.

Mechanism of Intestinal Spasms

  • Occur due to uncoordinated gut muscle contractions often exacerbated by emotional factors.

III Experiment # 8 Hypoglycemic Property

Overview of Diabetes Mellitus

  • Characterized as elevated blood glucose due to inadequate insulin secretion or action.

Classical Symptoms

  • Polyuria, Polydipsia, Polyphagia.

Screening Methods for Hypoglycemics

  • Various experimental models including Alloxan-Induced, Streptozocin-Induced, and others to study different diabetes types.

IV Experiment # 9 Inflammation Anti-inflammatory Property

Understanding Inflammation

  • Response to tissue damage characterized by redness, swelling, heat, pain, and impaired function.

Cardinal Signs of Inflammation

  1. Rubor

  2. Tumor

  3. Calor

  4. Dolor

  5. Functio laesa

Anti-Inflammatory Agents

  • Used for rheumatoid arthritis, osteoarthritis, and localized musculoskeletal syndromes among others.

Classification of Anti-Inflammatory Agents

  1. NSAIDs: Various chemical classifications including Salicylates and COX-2 inhibitors.

  2. DMARDs: Methotrexate, Cyclosporine, etc.

  3. Glucocorticoids: Dexamethasone, Prednisone.