COMPOUND RECORD / PEP-8

Pep-8 (2013 series)Пеп-8

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What the studies found

Animal research · 2013

Animal-derived peptide preparations in rat hypoxia, behavior and blood studies

Pep-8 time to agonal breathing: 95 ± 12.5 to 655 ± 127.5 secondsPrinted day-21 coefficient 6.89×. Table 1 uses 95 ± 12.5 seconds as the baseline for all six arms in the second series.Baseline to day 21
Pep-8 horizontal activity and immobility: Activity 7% to 22%; immobility 52% to 21%Saline control activity rose from 13% to 16% and immobility fell from 45% to 40%.Baseline to day 21
Highest day-21 times in each series: Pep-6, 787 ± 413 s; Pep-12, 659 ± 67.8 sPep-8 and Pep-11 were close to Pep-12. The paper gives no between-arm significance tests.

The Pep-8 row gives 95 ± 12.5 seconds at baseline and 655 ± 127.5 seconds on day 21 at simulated 11,500 m altitude. Six rats per group received a 21-day rectal course. The paper omits the amount administered and the time-matched saline results for hypoxia.

More reported outcomes

Arms with lower day-21 than day-14 times: Pep-7, 187 to 170 s; Pep-9, 478 to 315 s; Pep-10, 363 to 280 sReported means from Table 1.
Pep-8 blood measurements after the course: Lactate 18.6 vs 19.2; hemoglobin 178 vs 180 g/LPep-8 versus saline. The lactate column omits its unit.

Study notes · methods, sources and limitations

Participants or model Three-month-old female Wistar rats, 200 ± 20 g, six per group in the active and saline conditions. Twelve active preparations were tested in two series.

Design The methods give six female Wistar rats per group. Pep-1 through Pep-12 or saline was administered rectally once daily for 21 days. The article gives no dose, concentration or administration volume for the active preparations or saline. Each rat was brought to a simulated altitude of 11,500 m at 165 m/s at baseline and on days 7, 14 and 21. The primary endpoint was time to agonal breathing. The paper defines first collapse and posture recovery but does not tabulate those endpoints. Blood was collected the day after the final test. Behavior was recorded over 30 minutes at baseline and day 21.

Important limitations

Table 1 repeats one baseline across Pep-1–6 and another across Pep-7–12. The paper gives no saline hypoxia trajectory and does not specify whether the series shared a control group. The printed coefficients are baseline-relative. The tables do not define the ± term or report arm-level statistical tests. The Pep-4 day-7 coefficient differs materially from the ratio of the printed means. Blood and behavior measurements do not establish muscle growth, long-term safety or human performance effects. The names Pep-8, Pept-8 and VIR-8 identify different records. Chemical equivalence remains unverified.
The printed coefficients describe changes relative to the displayed series baselines. The missing saline hypoxia results and unclear baseline pooling prevent estimation of a saline-adjusted effect. The study does not establish operational performance or human safety.

Biomeditsina. 2013;(1):6–15. · Publication record

Original source or citation ↗

Study results and tables ↗

01 / OVERVIEW

About Pep-8 (2013 series)

Names in this research collection

Pep 8 · Pep-1–12 series

A coded preparation from a 2013 screen of 12 animal-derived peptide preparations. The paper reports 655 ± 127.5 seconds to agonal breathing on day 21 in six female Wistar rats and lists 95 ± 12.5 seconds as the second series baseline.

Research background

Performance research in context

Military & occupational evidence map ↗

Compound class: Coded animal-derived peptide preparation
Research collection: Actoprotection & occupational pharmacology · editorial grouping
Research institutions: No institutional affiliation recorded
Source review: Review dates and the material assessed are listed with each publication below.

02 / HOW TO READ THE RESEARCH

Understanding the evidence

Human research Rat hypoxia study
Study methods Six rats per group; daily rectal administration for 21 days; dose amount unspecified
Independent replication Independent replication unresolved
Source access Full publisher issue in the Internet Archive, methods and four tables checked
Safety evidence Human safety unavailable

Open a topic for the evidence assessment.

More findings, background and history

What remains unclear

The available experimental studies leave human benefit and safety uncertain.

No human intervention report has been identified among the linked records; unclassified archival leads may remain. Several publications can describe the same participants.

Browse original study records ↗

03 / SOURCE RECORDS

Linked sources

Explore the research map and unresolved leads ↗

2013 · Animal-derived peptide preparations in rat hypoxia, behavior and blood studiesPep-8 time to agonal breathing: 95 ± 12.5 to 655 ± 127.5 seconds

2013Animal / experimentalFull text available

Animal-derived peptide preparations in rat hypoxia, behavior and blood studies

Coded peptides extracted from different livestock organs. The paper gives a 500–1,300 Da range for the series and does not specify the composition of Pep-8.

N. N. Karkishchenko, V. N. Karkishchenko, Kh. Kh. Semenov, G. D. Kapanadze, Yu. V. Fokin, O. V. Alimkina, A. O. Revyakin, O. I. Stepanova, E. L. Matveyenko, N. V. Kasinskaya, S. E. Dengina · Biomeditsina. 2013;(1):6–15.

Results and tables

Reported findings and study design

Reported findings

The methods give six female Wistar rats per group. Pep-1 through Pep-12 or saline was administered rectally once daily for 21 days. The article gives no dose, concentration or administration volume for the active preparations or saline. Each rat was brought to a simulated altitude of 11,500 m at 165 m/s at baseline and on days 7, 14 and 21. The primary endpoint was time to agonal breathing. The paper defines first collapse and posture recovery but does not tabulate those endpoints. Blood was collected the day after the final test. Behavior was recorded over 30 minutes at baseline and day 21.

Dose, route and schedule

Pep-1 through Pep-12 or saline was administered rectally once daily for 21 days. The article gives no dose, concentration or administration volume for the active preparations or saline.

Protocol source ↗ · Original methods, printed pp. 7–8

Results · Archived publisher issue, printed pp. 6–15. Methods and Tables 1–4 checked against the page images.
Measure	Result	Comparison, timing and statistics
Pep-8 time to agonal breathing	95 ± 12.5 to 655 ± 127.5 seconds	Printed day-21 coefficient 6.89×. Table 1 uses 95 ± 12.5 seconds as the baseline for all six arms in the second series. · Baseline to day 21
Pep-8 horizontal activity and immobility	Activity 7% to 22%; immobility 52% to 21%	Saline control activity rose from 13% to 16% and immobility fell from 45% to 40%. · Baseline to day 21
Highest day-21 times in each series	Pep-6, 787 ± 413 s; Pep-12, 659 ± 67.8 s	Pep-8 and Pep-11 were close to Pep-12. The paper gives no between-arm significance tests.
Arms with lower day-21 than day-14 times	Pep-7, 187 to 170 s; Pep-9, 478 to 315 s; Pep-10, 363 to 280 s	Reported means from Table 1.
Pep-8 blood measurements after the course	Lactate 18.6 vs 19.2; hemoglobin 178 vs 180 g/L	Pep-8 versus saline. The lactate column omits its unit.

Table 1 · Time to agonal breathing at simulated altitude

Table 1 · Time to agonal breathing at simulated altitude
Arm	n	Baseline (s)	Day 7 (s)	Day 14 (s)	Day 21 (s)	Printed coefficients, days 7 / 14 / 21
Pep-1	6	110 ± 65	250 ± 113	268 ± 204	435 ± 163	2.27 / 2.44 / 3.95
Pep-2	6	110 ± 65	210 ± 110	348 ± 244	470 ± 180	1.91 / 3.16 / 4.27
Pep-3	6	110 ± 65	315 ± 70	444 ± 154	515 ± 153	2.86 / 4.04 / 4.68
Pep-4	6	110 ± 65	280 ± 267	403 ± 241	740 ± 323	3.45 / 3.66 / 6.73
Pep-5	6	110 ± 65	320 ± 97	508 ± 185	742 ± 222	2.91 / 4.62 / 6.75
Pep-6	6	110 ± 65	348 ± 244	370 ± 270	787 ± 413	3.16 / 3.36 / 7.15
Pep-7	6	95 ± 12.5	135 ± 150.0	187 ± 71.3	170 ± 95.0	1.42 / 1.97 / 1.79
Pep-8	6	95 ± 12.5	183 ± 83.0	533 ± 213.8	655 ± 127.5	1.91 / 5.60 / 6.89
Pep-9	6	95 ± 12.5	390 ± 79.0	478 ± 98.8	315 ± 195.0	4.10 / 5.02 / 3.31
Pep-10	6	95 ± 12.5	175 ± 127.5	363 ± 214.4	280 ± 126.7	1.84 / 3.82 / 2.95
Pep-11	6	95 ± 12.5	214 ± 223.1	477 ± 262.5	650 ± 150.0	2.25 / 5.02 / 6.84
Pep-12	6	95 ± 12.5	307 ± 69.8	543 ± 101.3	659 ± 67.8	3.23 / 5.70 / 6.94
Saline control	6	Unlisted	Unlisted	Unlisted	Unlisted	Unlisted

The methods give the group sizes and rectal schedule. The dose amount is unavailable for every arm. Time values and coefficients are reproduced as printed. For Pep-4 on day 7, 280 ÷ 110 is about 2.55, whereas the printed coefficient is 3.45. The saline row marks missing results and was added for clarity.

Table 2 · Blood chemistry after the course

Table 2 · Blood chemistry after the course
Arm	Urea	Glucose	Lactate	Triglycerides
Saline control	320.4 ± 3.1	5.28 ± 0.15	19.2 ± 2.6	70 ± 4.1
Pep-1	318.5 ± 2.9	5.30 ± 0.16	20.5 ± 3.2	73 ± 4.5
Pep-2	325.7 ± 3.2	5.29 ± 0.16	21.0 ± 3.6	75 ± 4.7
Pep-3	330.1 ± 4.4	5.31 ± 0.18	19.8 ± 2.9	73 ± 4.5
Pep-4	322.0 ± 3.5	5.30 ± 0.17	19.5 ± 2.7	69 ± 3.9
Pep-5	316.4 ± 2.8	5.33 ± 0.20	17.5 ± 1.7	65 ± 3.5
Pep-6	315.1 ± 2.3	5.34 ± 0.22	17.8 ± 1.9	64 ± 3.4
Pep-7	324.5 ± 3.7	5.31 ± 0.19	19.9 ± 3.0	71 ± 4.3
Pep-8	319.9 ± 3.0	5.35 ± 0.24	18.6 ± 2.2	67 ± 3.6
Pep-9	321.7 ± 3.2	5.29 ± 0.16	20.3 ± 2.3	72 ± 4.3
Pep-10	322.8 ± 3.3	5.28 ± 0.15	21.1 ± 3.5	70 ± 4.1
Pep-11	317.3 ± 2.7	5.34 ± 0.22	17.9 ± 1.9	66 ± 3.6
Pep-12	318.9 ± 2.9	5.32 ± 0.21	18.7 ± 2.2	68 ± 3.7

The authors give no units for these four columns. They also give no pretreatment blood values or between-arm significance tests.

Table 3 · Blood counts after the course

Table 3 · Blood counts after the course
Arm	Red cells (10¹²/L)	Hemoglobin (g/L)	Hematocrit (%)
Saline control	10.2 ± 0.60	180 ± 10	51.4 ± 4.8
Pep-1	10.1 ± 0.58	180 ± 10	51.2 ± 4.6
Pep-2	9.8 ± 0.56	179 ± 9	51.3 ± 4.7
Pep-3	10.0 ± 0.57	178 ± 8	51.5 ± 4.9
Pep-4	9.9 ± 0.56	181 ± 11	51.4 ± 4.7
Pep-5	9.5 ± 0.50	180 ± 12	50.8 ± 4.3
Pep-6	9.4 ± 0.49	179 ± 9	50.6 ± 4.2
Pep-7	10.3 ± 0.61	182 ± 13	51.0 ± 4.5
Pep-8	9.8 ± 0.58	178 ± 8	50.7 ± 4.4
Pep-9	10.4 ± 0.62	184 ± 17	51.5 ± 4.9
Pep-10	10.1 ± 0.58	181 ± 12	51.7 ± 5.0
Pep-11	10.0 ± 0.57	179 ± 9	50.8 ± 4.3
Pep-12	9.8 ± 0.58	183 ± 15	50.9 ± 4.4

Table 4 · Behavior at baseline and day 21

Table 4 · Behavior at baseline and day 21
Arm	Immobility (%)	Horizontal activity (%)	Grooming (%)
Saline control	45 → 40	13 → 16	19 → 22
Pep-1	30 → 19	11 → 25	18 → 21
Pep-2	32 → 14	16 → 24	18 → 23
Pep-3	36 → 29	13 → 22	17 → 19
Pep-4	49 → 26	9 → 24	20 → 20
Pep-5	57 → 35	6 → 22	11 → 15
Pep-6	41 → 20	4 → 23	18 → 23
Pep-7	44 → 33	12 → 24	18 → 19
Pep-8	52 → 21	7 → 22	24 → 28
Pep-9	26 → 17	14 → 26	9 → 23
Pep-10	23 → 18	11 → 24	14 → 25
Pep-11	49 → 28	5 → 23	20 → 24
Pep-12	55 → 26	4 → 22	15 → 21

Percentages of the 30-minute observation session. The paper gives no uncertainty terms or arm-level significance tests for behavior.

The printed coefficients describe changes relative to the displayed series baselines. The missing saline hypoxia results and unclear baseline pooling prevent estimation of a saline-adjusted effect. The study does not establish operational performance or human safety.

Source for these results ↗ · Reviewed 2026-11-11

Population / setting: Three-month-old female Wistar rats, 200 ± 20 g, six per group in the active and saline conditions. Twelve active preparations were tested in two series.
Source reviewed: Archived publisher issue, printed pp. 6–15. Methods and Tables 1–4 checked against the page images.

Study limitations

Table 1 repeats one baseline across Pep-1–6 and another across Pep-7–12. The paper gives no saline hypoxia trajectory and does not specify whether the series shared a control group. The printed coefficients are baseline-relative.
The tables do not define the ± term or report arm-level statistical tests. The Pep-4 day-7 coefficient differs materially from the ratio of the printed means.
Blood and behavior measurements do not establish muscle growth, long-term safety or human performance effects.
The names Pep-8, Pept-8 and VIR-8 identify different records. Chemical equivalence remains unverified.

Reviewed 2026-11-11.

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Pept-8 (2012 series) research ↗

Coded animal-derived peptide preparation

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Pep-8 (2013 series)Пеп-8

What the studies found

Animal-derived peptide preparations in rat hypoxia, behavior and blood studies

About Pep-8 (2013 series)

Names in this research collection

Performance research in context

Understanding the evidence

What remains unclear

Linked sources

Animal-derived peptide preparations in rat hypoxia, behavior and blood studies

Reported findings and study design

Dose, route and schedule

Related compound research

Pept-8 (2012 series) research ↗