Pharmacology – I (Practical) [PHL 313] Dr. Mohd Nazam Ansari

Lab – 1: Different Laboratory Animals and Their Application PHARMACOLOGY is the branch of science which deals with study of drugs on living systems EXPERIMENTAL PHARMACOLOGY: deals with study of effect of various Pharmacological agents on different animal species AIMS : To find out the therapeutic agent suitable for human use To study the toxicity of the drugs To study the mechanism and site of action of drugs PHARMACOLOGY Discovery of new drugs or to study the actions of existing drugs Preclinical Clinical Two ways Phase -1,2,3,4 Intact animal study – invivo Isolated organ study – invitro

Clinical Trial Phase I: Phase II: A small group (20-100) of healthy volunteers The safety, tolerability, pharmacokinetics, and pharmacodynamics of a drug These trials are often conducted in an inpatient clinic, where the subject can be observed by full-time staff Pay ranges from a small amount of money for a short period of residence, to a larger amount of up to approx $6000 depending on length of participation. Phase II: Safety assessments in a larger group of healthy volunteers and patients (20-300)

Phase III: Randomized controlled multicenter trials on large patient groups (300–3,000 or more depending upon the disease/medical condition studied) Phase III trials are the most expensive, time- consuming and difficult to design and run, especially in therapies for chronic medical conditions   Phase IV: Is also known as Post Marketing Surveillance Trial. Harmful effects discovered by Phase IV trials may result in a drug being no longer sold, or restricted to certain uses

Experimental pharmacology – great importance Experimenter should take outmost care Sacrificing – human Euthanasia – painless killing Laboratory animals – breaded and handled in laboratory Rat Mice Guinea pig Rabbits Frogs Other: Cat, Dog, Monkey, Pigeon etc.

RATS Species – Rattus norvegicus Albino rats of Wistar strain are commonly used Other strains – Wistar kyoto rat Sprague Dawley rat Biobreeding (BBDP) rat Long-Evans rat Zucker rat Genetically modified rats Hairless rats (Rowett nude, Fuzzy, Shorn) RCS rats

Wistar rat Wistar rats are strain of albino rats belonging to the species Rattus norvegicus. This strain was developed at the Wistar Institute in 1906 for use in biological and medical research, and is notably the first rat strain developed to serve as a model organism at a time when laboratories primarily used Mus musculus, or the common House mouse. The Wistar rat is currently one of the most popular strains used for laboratory research. It is characterized by its wide head, long ears, and having a tail length that is always less than its body length. The Sprague Dawley rat and Long-Evans rat strains were developed from Wistar rats. Wistar rats are more active than other strains like Sprague Dawley rats.

Sprague Dawley rat The Sprague Dawley rat is multipurpose breed of albino rat used extensively in medical research. Its main advantage is its calmness and ease of handling. The adult body weight is 250–300g for females, and 450–520g for males. The typical life span is 2.5–3.5 years. These rats typically have increased tail to body length ratio compared with Wistar rats.

Biobreeding rat Biobreeding Diabetes Prone rats (or BBDP rat) are inbred rat strain that spontaneously develops autoimmune Type 1 Diabetes. BB rats are used as an animal model for Type 1 diabetes. The strain re-capitulates many of the features of human type 1 diabetes, and has contributed greatly to the research of T1D pathogenesis

Long-Evans rat Long-Evans rats are strain of rats belonging to the species Rattus norvegicus. This strain was developed by Drs. Long and Evans in 1915 by crossing several Wistar females with a wild gray male. Long Evans rats are white with a black hood, or occasionally white with a brown hood. They are utilized as a multipurpose model organism, frequently in behavioral and obesity research.

Zucker rat Zucker rats were bred to be a genetic model for research on obesity and hypertension. There are two types of Zucker rat: a lean Zucker rat; and the characteristically obese (or fatty) Zucker rat, capable of weighing up to 1 kilogram (2.2 lb)—more than twice the average weight. Obese Zucker rats have high levels of lipids and cholesterol in their blood, and gain weight from an increase in both the size and number of fat cells. Obesity in Zucker rats is primarily linked to their hyperphagic nature, an excessive hunger.

Hairless rats Hairless rats provide researchers with valuable data regarding compromised immune systems and genetic kidney diseases. The more common ones are denoted as rnu (Rowett nude), fz (fuzzy), and shn (shorn). Rowett nudes, first identified in 1953 in Scotland, have no thymus. The lack of this organ severely compromises their immune system, infections of the respiratory tract and eye increasing the most dramatically. Fuzzy rats were identified in 1976. The leading cause of death among these rats is a progressive kidney failure. Shorn rats were bred from Sprague Dawley rats in 1998. They also suffer from severe kidney problems.

RCS rats The Royal College of Surgeons (RCS) rat is the first known animal with inherited retinal degeneration.

ADVANTAGES AND CHARACTERISTICS: small in size drug to be tested required in small quantity vomiting center is absent – oral administration can be done gall bladder and tonsils are absent Continuous flow of bile into intestine, This facilitates the study of the drugs acting on bile, cholesterol reabsorption etc. In stomach, fundus and pyloric parts have clear lining between them Gastric acid secretion is continuous

EXPERIMENTAL USE: (Adult weight: 200-250g, Age: 1.5 months) Psychopharmacological studies Study of analgesics and anticonvulsants Bioassay of various hormones, such as insulin, oxytocin, vasopressin Isolated tissue preparations like uterus, stomach, vas deferens, aortic strip, heart etc. Chronic study on blood pressure Gastric acid secretion studies Hepatotoxicity studies Acute and chronic toxicity studies

MICE ( Mus musculus) Swiss albino mice are commonly used species Other strains are – Balb/C and C-57 ADVANTAGES AND CHARACTERISTICS: Smallest Less drug required Easy to handle Cheap EXPERIMENTAL USES: (Adult weight: 20-25g, Age: 1 month) Toxicological studies specially acute and subacute toxicity Bioassay of insulin Screening of analgesic and anticonvulsant Screening of chemotherapeutic agents Studies related to genetics and cancer research Drugs action on CNS

GUINEA PIGS ( Cavia porcellus ) ADVANTAGES AND CHARACTERISTICS : Docile animals Highly susceptible to TB and anaphylaxis Highly sensitive to histamine, penicillin Required exogenous vitamin C in diet EXPERIMENTAL USES (Adult weight: 400-600g, Age: 3 months) Evaluation of bronchodilators Study of histamine and antihistamines Bioassay of digitalis Evaluation of local anesthetics Hearing experiments because of sensitive cochlea Isolated tissues especially ileum, tracheal chain, heart etc. Study on TB and ascorbic acid metabolism

RABBITS (Lupas cuniculus) ADVANTAGES AND CHARACTERISTICS : Docile animal with large ears New Zealand white strains are widely used It has huge caceum and long appendix Enzyme atropine esterase is present in rabbit liver and plasma so it can tolerate large doses of belladona (atropine) EXPERIMENTAL USES (Adult weight: 1.5-3.0 Kg, Age: 5-6months) Pyrogen testing Bioassay of anti-diabetic, and sex hormones Drugs used in glaucoma Pharmacokinetic studies Studies related to antifertility agents Isolated preparations like heart, duodenum, ileum, etc. Study on local anaestetics Study on miotic and mydratics

FROGS (Rana tigrina) ADVANTAGES AND CHARACTERISTICS : Used before 200 years Easily available during rainy season Amphibian animal and safe to handle Cannot breed in lab EXPERIMENTAL USES Isolated preparations, rectus abdominis muscle & heart Drugs acting on CNS Drugs acting on NMJ

Housing & Maintenance of Laboratory animals Institutional or departmental ethical committee Animal House Separate building at a quiet atmosphere, undisturbed by traffic Should be hygienic & protected from extremes of climate Good ventilation Exhaust fan Roof should be 10 feet high Large no. of small rooms Quarantine area Extra space for office, surgery, washing and sterilizing, kitchen & incinerators No overcrowding permitted Animal Cages: Plastic, galvanised iron, aluminium etc. Anodised aluminium is best Size Tray for food and water bottle Bedding: rice husk or paper Proper labeling

Clean drinking water Ventilation Food Free movement Resting Following requirements should be stressed on mind: Clean drinking water Ventilation Food Free movement Resting Temperature Humidity Diseases Handling Mental Health

Housing and Routine Care: Animal Crowding Animal crowding in a cage affects environmental quality (the accumulation of urine, for example, leads to excess ammonia and moisture). Crowding can also cause newborn pups to be injured or killed. Crowding is a special concern for multiple litters in a cage since pups grow very quickly and rapidly increase their output of excreta. In particular, if the mother is about to give birth to a second litter, the first litter should be weaned and removed to new cages to prevent smothering and trauma of the newborns.

Routine Sanitation Routine sanitation and environmental controls are necessary for protecting animal health and for minimizing the introduction for non-experimental variables which could undermine the quality of research data. Sanitation schedules vary according to the type of mouse caging. Based on the types of caging and bedding in use at your facility, your institution will have a standard operating procedure (SOP) on the sanitation schedule for mouse cages.