Source comparison
MK-677 Animal Research: Study Design Comparison
Beagle dogs (Merck, 1995) 0.1–1.0 mg/kg oral Serum GH & IGF-1 elevation GH increased 97–130%, IGF-1 increased 39–79% at trough 7 days Established dose-response relationship and confirmed oral bioavailability Aged rats (JBMR, 1998) 3 mg/kg oral daily Femoral &
This comparison does not assign a generated winner or score.
- Beagle dogs (Merck, 1995)
- 0.1–1.0 mg/kg oral
- Serum GH & IGF-1 elevation
- GH increased 97–130%, IGF-1 increased 39–79% at trough
- 7 days
- Established dose-response relationship and confirmed oral bioavailability
- Aged rats (JBMR, 1998)
- 3 mg/kg oral daily
- Femoral & lumbar BMD
- BMD increased 8.4% femur, 11.7% lumbar spine
- 12 weeks
- Demonstrated anabolic bone effects without proportional resorption increase
- Ovariectomized rats (Endocrinology, 2000)
- 2 mg/kg oral daily
- Trabecular bone volume
- Partial reversal of estrogen-deficiency bone loss
- 16 weeks
- Showed skeletal effects persist in hormone-depleted models
- Calorie-restricted rats (Johns Hopkins)
- Lean mass retention & nitrogen balance
- Maintained 94% lean mass vs 78% placebo during 40% restriction
- 4 weeks
- Confirmed anti-catabolic effect independent of caloric surplus
- Rhesus monkeys (Endocrine Society, 2003)
- 0.5–2.0 mg/kg oral
- 24-hour GH pulsatility profile
- Amplitude increased 89%, frequency unchanged, no tachyphylaxis
- 90 days
- Validated that chronic use doesn't suppress endogenous pulsatility
- Fasted rats (metabolic chamber)
- 1.5 mg/kg oral
- Muscle proteolysis markers
- 3-methylhistidine excretion reduced 31% vs fasted controls
- 72 hours
- Quantified reduction in contractile protein breakdown during catabolism