NCSU Course ZO410 Lecture:
Hormones & Behavior

Neural vs. Hormonal Characteristics
Voluntary Control
Chemical Release
Signal Speed

Mouse Intrauterine Position example
- fetus may be permanantly altered by neighboring fetuses hormones
0M, 1M, 2M females and males-- characteristics

Review of Endocrinology

A. Definitions

  • hormone
  • endocrine glands

    • B. Modes of Action of Hormones

  • Peptide:

    •        -specific, second messenger involved, water-soluble
  • Steroid:

    •        - general, lipid-soluble, directly to DNA

    C. Invertebrate hormone-behavior relationships

    D. Vertebrate endocrine system

    1. Hypothalamo-Pituitary System
  • anterior/posterior pituitary
  • releasing factors to anterior via blood

    •                 -examples of releasing factor, hormone, target organ
  • feedback loops
  • pulsatile release
  • neurons to posterior pituitary

    •                 -oxytocin, vasopressin
    2. Endocrine Glands
  • Chart, page 107 in textbook
  • note sex differences/similarities in steroid hormones

    • E. Estrus Cycles

    Estrus vs. Estrous

    1. Characteristics of etrous females
    2. Rat estrus cycle
    3. Human menstrual cycle
    4. Spontaneous vs. Induced Ovulators

    Other female behavioral/hormonal effects:
        1. Lee-Boot Effect
        2. Whitten Effect
        3. Bruce Effect
        4. Vandenbergh Effect

    E. Organizational effects of hormones  (Vertebrates)

  • Goy, Young, Phoenix, and Gerall- 1959

    •     -prenatal T masculinized female guinea pigs
        -prenatal hormones alter structure of nervous system
     
  • examples of work demonstrating organizational effects

    •     -IUP
        -castration and hormone replacement
     
  • effects occur early in life, are permanent

    •  

    F. Activational effects of hormones

  • Castration and ovariectomies remove copulatory behaviors

    •     - hormone replacement restores
     
  • high hormone levels "activate" specific patterns of sexual behavior
  • transient effects

    •  
  • original work on roosters
  • hamsters, flank gland
  • rhesus monkey

    •     - relationship between mounting and T
        - environmental influence
        - presence of females
     
  • estrogen and female memory

    •  
  • humans and T levels?

    • Behavioral - hormonal coordination

    I. Reproductive patterns. Three Kinds:

    A. Hormone Associated:
    Crews, 1987 - Green anole lizard, Anolis carolinsensis
    Reproductive cycle of anole
    Effect of castration and T replacement
    Effect of behavioral stimulation from the male
    Endocrine Coordination
    B. Hormone Dissociated
    Red-sided garter snake, Crews, 1986
    Manitoba
    Mating
    C. Constant Reproductive condition
    Often in harsh environments
    Remain in "ready " condition - only need trigger
    Zebra finch ( Western Australia)
    Rhesus monkey
    La Parguera
    -Free ranging rhesus monkeys
    -Seasonal breeder
    -Experiment
    -Yerkes results
    Principle of Endocrine Coordination

    II. Stress

    Hormones involved: General Definition:
    Stressor: Any environmental perturbation which disrupts homeostasis
    Stress response: Set of physiological adaptations which the body consistently musters to restablish homeostasis
    Hans Selye - General Adaptation Syndrome (1936)

     
    End of Lecture-Hormones & Behavior subsite. Move to: ZO 410's Course Homesite.
    Original author this subsite (lhab.html)= calswww@ncsu.edu, originally posted 7-95 under direction of Dr. John G. Vandenbergh. Updated 8-30-01 by M. Dean.