Understanding Glucocorticoid Effects
Glucocorticoids are steroid hormones, often released during stress, that play a significant role in regulating the immune system and brain function, key components of the psychoneuroimmunological system. We need to determine which of the given options is least affected by these hormones.
Impact on Immune Cells
- T-cells: Glucocorticoids have well-documented immunosuppressive effects on T-lymphocytes, inhibiting their activation and proliferation.
- B-cells: Similarly, glucocorticoids can suppress the function of B-lymphocytes, affecting antibody production.
Impact on Neurons
Hippocampal neurons are known to possess glucocorticoid receptors. Glucocorticoids influence neuronal activity, plasticity, and stress responses within the hippocampus.
Posterior Pituitary Function
The posterior pituitary gland primarily releases hormones synthesized in the hypothalamus, namely Antidiuretic Hormone (ADH) and Oxytocin. While complex feedback mechanisms exist within the neuroendocrine system, the posterior pituitary's direct functional output is not considered a primary target of glucocorticoid action in the same manner as immune cells or specific brain regions like the hippocampus.
Conclusion on Glucocorticoid Effects
Based on their established roles, T-cells, B-cells, and hippocampal neurons are significantly influenced by glucocorticoids. The posterior pituitary is the component least directly affected.
Important Questions from Immune System
- Which of the following is correct about the impact of stress on immune system of an individual?
- Brief stress enhances the activity of immune system as evidenced by the action of
- Choose the correct sequence of response of immune system
A. Synthesizes antibodies which comprises immunoglobulins
B. Immune system identifies foreign substances in the body
C. Immunoglobulins specifically designed to bind the antigens
D. Destroy the antigens
Choose the correct answer from the options given below: There are number of specific T cell surface molecules involved in various functions of adaptive immune response. Column X represents a list of T cell surface molecules and Column Y with the possible functional characteristics:
Column X
Column Y
A.
T cell receptor
(i)
binds to CD40 on B cells and APCs and triggers activation of APCs and activation/differentiation of B cells.
B.
CD28
(ii)
binds to MHC class I molecules and restricts I cytotoxic cells to recognizing only peptide presented on MHC class I
C.
CD8
(iii)
binds to B7 - 1, 2 or CD80/86 on B cells and APCs, which triggers T cell activation.
D.
CD154
(iv)
consists of two poly-peptide chains α and β and some consist of poly-peptide chains γ and δ.
Which of the following option has all correct matches?
Which one of the following influenza A virus subtypes caused severe avian flu and was responsible for disease outbreak in the year 1997 in Hong Kong?
