â– LECTURE OVERVIEW: Benign Prostatic Hyperplasia (BPH) is an age-related, non-malignant proliferation of the prostatic stromal and epithelial cells.
â– PATHWAY ANALYSIS:
1. Transition Zone: Hyperplasia occurs selectively in the central periurethral Transition Zone, compressing the prostatic urethra and obstructing urine outflow.
2. Dihydrotestosterone (DHT) Influence: Driven by DHT, synthesized from testosterone by 5-alpha-reductase in prostatic stromal cells.
3. Lower Urinary Tract Symptoms (LUTS): Presents with urinary frequency, urgency, nocturia, a weak urinary stream, hesitancy, and incomplete emptying.
4. Pharmacotherapy Approaches:
- Alpha-1 Adrenergic Blockers: Selectively block alpha-1A receptors on the prostatic urethra and bladder neck, relaxing smooth muscle to rapidly improve urine flow.
- 5-Alpha-Reductase Inhibitors: Block 5-alpha-reductase, preventing testosterone's conversion to DHT to shrink the prostate over 6-12 months.
â– THERAPEUTIC TARGETS & MANAGEMENT:
Primary pharmacological intervention aims to restore physiological homeostatic balance. This is achieved by either competitively blocking receptor sites, allosterically inhibiting enzymes, or supplementing missing metabolic products.
â– MOLECULAR PATHWAY DYNAMICS:
Intracellular cascades undergo profound modifications, altering secondary transcription levels and receptor presentation on cellular membranes.
[HY-BOARD-1064]
🌟 Dynamic Clinical Key:
Alpha-1 blockers (e.g., Tamsulosin, Silodosin) provide rapid symptom relief but do not shrink the prostate. 5-alpha-reductase inhibitors (e.g., Finasteride, Dutasteride) are used for long-term reduction of prostate size, helping to prevent acute urinary retention. Absolute contraindications include pregnancy, renal insufficiency, or concurrent use of metabolic inhibitors. Therapeutic molecules targeting upstream signaling components demonstrate superior efficacy profiles.